Moral Philosophy and Modern Science

From Natural Moral Law to Moral Capacity

Note: Dr. Marian Hillar has kindly made the introduction to his upcoming book available to the Spiritual Naturalist Society for our educational archives. The book is titled, “The Historical Development Toward a Non-Theistic Humanist Ethics: Essays from the Ancient Stoics to Modern Science“…

This book is a collection of essays published previously on various aspects of moral philosophy and arranged thematically and in chronological order showing our increasing comprehension of human moral behavior. There is one theory explaining our moral behavior that seems to be meandering throughout the history of ideas and that led eventually to scientific explanation of human moral behavior and postulating the evolutionary biological process as its origin. Natural moral law theory in its modern interpretation may be considered as the culminating point of intellectual attempts to explain moral behavior, today not only interpreted in a very narrow sense of human behavior, but also encompassing other forms of animal life. For life constitutes a continuum of a phenomenon with gradation of properties and characteristics. Thus it seems proper that we attempt in this introduction to give a review of various interpretations of the natural moral law.


Since time immemorial humans have been preoccupied with their own behavior and attitudes towards other humans, the rest of the animate world, and the surrounding environment. This is attested by the oldest written documents from the Mesopotamian, Mediterranean, and Far Eastern regions of the World.1 In every culture we find the practical injunction for moral behavior expressed in the “Golden Rule,” a universal principle guiding human behavior. This rule is expressed in religious injunctions as well as in philosophical analyses wherever such attempts were made as is attested again by the history of philosophy.2

When answering the questions of how to live our lives and treat others, philosophers developed several theories such as hedonism, psychological egoism and altruism, ethical egoism, consequentialism and utilitarianism, deontological theory (Kant’s well-being theory), virtue ethical theory, contractarianism and social contract theory, prima facie duties theory, natural law theory.3 The natural law theory seems to be the most fundamental-going to the roots conditioning human behavior and all other philosophical speculations. The idea of a natural law in morality governing our behavior has a long history and was interpreted or understood in a variety of ways. Though it has limited value for a formulation of detailed practical maxims to conduct human behavior, nevertheless, it is still used by contemporary religious leaders to argue in defense of particular moral assumptions based on their theological worldview. It has, however, a great historical value for the evaluation of validity of secular philosophical intuition. For modern science, starting with Darwin and his insights into evolution of man, has reached a level of sophistication and precision whereby is able to explain the naturalistic basis for the intuition of philosophers.4 Consequently, the concept of moral law acquires a new meaning and is interpreted as the natural capacity for the moral behavior that forms the foundation of the behavior of living things, especially higher animals and humans.

Early Societies: The Rule of Law

In all early societies the rules governing them were customs based on traditional and conventional beliefs of what was right or true. Subsequently, they were drawn up and codified as obligatory norms backed by the authority of the state or ruler. Thus the rules of the political society mirrored the moral sensitivity of people who formed it. In primitive societies there was no difference between the moral rules expressed in customs and the laws established in codified norms.5 Such a situation presupposed the existence of an active designer or giver of these laws, and as long as theistic religion was the governing force this designer was god or divinity. Such view was a common knowledge in ancient Greek society and we find expression of it in Heraclitus (540-480 B.C.E.)6 and Hesiod (b. ca 750 B.C.E.),7 who declared that Zeus has laid down a law for all men that unlike the beasts they should possess justice.

Sophists and the Nomos Physis Antithesis in the Fifth Century

This outlook was changed in the first half of the fifth century B.C.E. when social and political changes as well as new ideas about the external world developed by the Pre-Socratic philosophers-scientists led to the rise of intellectual ferment, the age of the ancient Enlightenment.8 Doubts introduced by the Pre-Socratic philosophers about the role of divinity in the natural world led to its replacement by natural necessity as cause and introduction of relativity to social, political, and ethical conceptions. The so-called Sophists who changed the previous focus of interest from the physical reality to the affairs of humans played the primary role in this movement.9

They contrasted nomos with physis – they distinguished between the human laws and laws governing the nature of physical reality. They considered our human laws, customs, and religious beliefs changeable because they were not rooted in the natural order.10 They looked for explanations and guidance to such matters as politics and morals, and they attempted to develop general theories of human nature, metaphysics, and epistemology.11

At the same time, Sophists recognized the existence of the unwritten and necessary natural moral law,12 though considered as originating from gods. They designated an eternal moral principle, universally valid and overruling the positive laws of men. Its conception is well described in Sophocles’s Antigone or in Euripides’s Hecub. However, the popular beliefs in gods became undermined by speculation of the naturalists and satirical writers like Aristophanes.

Plato (427-347 B.C.E.) rejected the idea that morals and moral law are changing.13 He refers us to the unchanging reality, the reality of the Forms (eidos), which is accessible only to reason and of which human societies are largely ignorant. Human behavior in societies is not only subject to the rules established by men in societies, but also to the universal law which is unwritten and to which even gods are subject.14 Thus it seems that Plato laid the foundation for this original concept of the unchanging natural moral law as part of our natural world.

Aristotle: Changing Nature and Man as a Rational Animal

Next to dwell on the topic of tnatural law was Aristotle (384-322 B.C.E.), who distinguished in his Nicomachean Ethics between conventional or legal justice, and natural justice. However, they are not unchangeable.15

Aristotle could arrive at such a conclusion since he viewed nature from the biological perspective of observing natural phenomena. Biological changes are natural because they derive from the inner working of natural reality, from its latent principles.

If such a view is correct, the question now arises what is human nature, what is human characteristic or human function and the principle that makes us humans? After a lengthy discussion and comparison with other forms of life, Aristotle states that the proper nature of man is “an active life of the rational element.” And he differentiates between “activity” directed by reason and mere passive “possession” of reason:

The rational element has two parts: one is rational in that that it obeys the rule of reason, the other in that it possesses and conceives rational rules. Since the expression “life of the rational element” also can be used in two senses, we must make it clear that we mean a life determined by the activity, as opposed to the mere possession, of the rational element. For the activity, it seems, has a greater claim to the function of man … the good of man is an activity of the soul in conformity with excellence or virtue, and if there are several virtues, in conformity with the best and most complete.16

The Stoic Philosophy

By stating that reason and rationality is the distinctive human characteristic, Aristotle set the foundations for formulations of the natural law as governing the world and humans, which was postulated by the Stoics and explicitly formulated by Cicero. The Stoic philosophy was the most important and influential development in Hellenistic philosophy, and it affected Christian writers and their moral thinking as well as many philosophers.17 It was revived in the deism and naturalism of the Enlightenment and continues to affect modern thinking as well.18

1. Interdependence in nature

The Stoics were the first philosophers who maintained systematically that all things in the world are necessarily interrelated: “from everything that happens something else follows depending on it by necessity.”19 Chance for them was simply a name for undiscovered causes.20

This idea may partially correspond to modern concepts of mutual interdependence in social, political, economical, moral, and ecological terms. Thus it had deep significance for the Stoics since it also included a moral and psychological sense of relating to one’s self, society, and the world. To be a happy and good man meant for the Stoics to be related to the universe, “to feel at home in the universe,” and to other human beings in a manner according to reason. Marcus Aurelius wrote: “Neither can I be angry with my brother or fall foul of him; for he and I were born to work together…,”21 and, “The chief good of a rational being is fellowship with his neighbors – for it has been made clear long ago that fellowship is the purpose behind our creation.”22

We find this Stoic principle repeated almost verbatim by Jürgen Habermas as the only and sufficient justification for the morality and ethics. He develops it into his “moral principle of universalizability,” whereby an individual is integrated into a social order and his moral obligation arises from the process of socialization. Before Habermas, Immanuel Kant developed the same principle into his logical maxim of “categorical imperative.”23

Individualism was antithetical to Stoicism. Since all things are interconnected they have one universal cause that was “creative reason” or the logos, which is the indwelling cause of all things.24 This model was applied to human action25 in which we have to distinguish the external stimulus from the mind’s response. The stimulus causes an impression which presents the mind with a possible course of action. It is up to the man how he is to respond.26 A deliberate act is thus a combination of an impression and an internal response exactly as Aristotle would define it.27 The Stoics and Aristotle did not look for a criterion of voluntary action as in “being free to act otherwise.”28 Thus the character of an individual was the general cause of one’s actions that was a result of heredity and environment.29 Moral corruption was traced by the Stoics to persuasiveness of external affairs and communication with bad acquaintances.30 In the last analysis, the logos was the determining factor since it was all-pervasive. An individual’s logos, assuming the particular identity, is the real self of an individual. Its logos is the self-determining factor. Thus the Stoic philosophy of nature provided a rational explanation for all things in terms of the intelligent activity of a single entity that is coextensive with the universe.

2. The problem of evil in the universe

In the Stoic worldview the uncreated and imperishable Nature, God, Pneuma, or the universal Logos exercises its activity in a series of eternally recurrent world-cycles beginning and ending as cosmic pure fire with each world. Within each cycle, Nature disposes itself in different forms: animal, vegetable, and mineral. Man is just one class of animals that is endowed with a share of its own essence, reason, in an imperfect but perceptible form. Nature as a whole is a perfect, rational being; all of its acts are the ones that should commend themselves to rational beings. If the “world is designed for the benefit of rational being” is there nothing bad within it? Here, Stoics approach the problem of evil in the world and showed their utmost ingenuity.31 Stoics claimed that nothing is strictly bad except moral weakness. Natural disasters are not bad per se and they do not undermine Nature. They have their own rationale peculiar to themselves for, in a sense, they occur in accordance with universal reason and as such they are not without usefulness in relation to the whole. They are not Nature’s plan but an unavoidable consequence of the good things that are. Thus Nature plays a double role in any causal explanation.32 This was an optimistic philosophy that oriented life in accord with Nature and the development of virtues – the perfection of human nature that is reason.33 The moral ideal thus became a virtuous person who knows the good and acts in accordance with it following the rational order.

3. Human Nature

Concerning human nature, the Stoics gave the traditional answer that it is the Mind that distinguished humans from other things, a concept borrowed from Diogenes the Cynic (b. ca 412 B.C.E.). This rationality was understood as the practical wisdom of living in accordance with Nature. Individual human beings share this rational principle with Nature, and thus it is a part of the world. Humans are endowed in varying degrees with “seed powers” (or spermatikoi logoi) which were part of the principle or logos of God. Cosmic events and human actions are both consequences of one thing, the logos. Therefore, humans have the ability to know the rational order governing the world, and this order is conceived as life-supporting breath or pneuma by analogy to the individual living creature. In Plato’s idealism, mind and body were distinct. Modern psychology, physiology, neurology, and psychiatry provide evidence that there is little reason to deny that mental computations are purely physical processes in the central nervous system.34 This Stoic concept of rationality acquired a new meaning in Habermas’s interpretation as the communicative action in a social context representing a point of convergence for various cultures and societies. This convergence is based on the role played by universal concepts, such as truth, rationality, justification, and consensus that are found in every community. They form a “grammar” for discourse by analogy to Chomsky’s universal language grammar:

We may assume that the know-how informing argumentative practices represents a point of convergence where participants, however diverse their backgrounds, can at least intuitively meet in their efforts to reach an understanding. In all languages and in every language community, such concepts as truth, rationality, justification, and consensus, even if interpreted differently and applied according to different criteria, play the same grammatical role.35

Stoic theory thus anticipated the modern concepts as mind and matter are two constituents or attributes of one thing, the body. A man is a unified substance, but what he consists of is not uniform. All human attributes, according to the Stoics, are due to the permeation of matter by pneuma. The soul of man is a portion of the vital, intelligent, warm pneuma (breath) which permeates the entire cosmos36 and the body. At death, the soul survives for a limited time only. Moreover, pneuma does not endow everything with life – only individual things with pneuma of a certain kind of tension are endowed with life. Depending on the type of tension, things are endowed with different types of life but only animal life and man have soul.37 The soul has eight faculties, five of them being the senses while the other three are the faculties of reproduction, speech, and the governing principle – the so-called hegemonikon – “capable of commanding,” and “the most authoritative part of the soul.”38

4. The Stoic Ethics

The governing principle logos is the seat of consciousness and consists of all the functions which we would associate with the brain. One function is called “impulse,” (hormē) “a movement of thought towards or away from something”39 which is initiated by an impression. Impression and impulse provide causal explanations of goal-oriented animal movements. Creatures are genetically determined to show aversion and preference. The technical term describing this relationship to the environment is oikeiōsis, a self-awareness and the behavior depends on animal or human recognition of the object as belonging to itself by its faculty of “assent.”40 However, we are not impelled or repelled by things that we fail to recognize as a source of advantage or harm.41 This faculty coerces us to select things necessary for self-preservation and not necessarily by reason. An infant is “not yet rational,” and it takes about 7 years to develop the logos.42 Automatic impulse thus governs the behavior of humans in the earliest years, the first thoughts concerning self-preservation. Gradually, as the child develops, its governing principle is modified by accretion of the logos, and then “reason [becomes] supreme as the craftsman of impulse.”43 Reason, however, does not destroy the earlier impulses but rather they are taken over by it.

Human nature therefore develops from irrationality to a structure governed by reason, which in turn brings a change in the direction of impulse.44 In particular new objects of desire develop and virtue becomes a human characteristic.45 This process is a natural development towards a moral life described by Epictetus of Hierapolis (60 – ca 120 C.E.):

But God has introduced man, as a spectator of himself and of his works; and not only as spectator, but as an interpreter of them. It is therefore shameful for a man to begin and end where irrational creatures do. He is indeed to begin there, but to end where nature itself has fixed our end; and that is, in contemplation and understanding, and in a scheme of life harmonious with nature.46

Attainment of rationality alters the whole structure of a man’s governing principle. Human behavior is a mode of rational conduct, which is the use of faculties for the purposes designed by universal natural law.47 Even the actions that we usually describe as irrational impulses are in fact governed by rational principle in the sense that they produce a judgment (intellectual assent) that moves to action, the movement of the soul. So the distinction is between the right reason (eulogos) and the wrong reason (alogos).48 Therefore, everything that we do is rational in a sense, but the sage or the good man is the criterion because he alone has the right reason49 in a consistent way.50 We fluctuate between right and wrong reason and make moral progress not by extirpating desires and emotions but by making them increasingly consistent with the right reason.51

The interconnection between all events and things in the universe constitutes its determinism, i.e. the sequence between the causes and the effects. The Stoics believed that the universe operates in an orderly fashion and is intelligible, which means that if we knew all the preceding causes we would be able to predict future events. The ordered interweaving of causes and events was termed “fate” (heimarmēnē).52 Their concept of cause (aitía) was different from the Aristotelian one, the novelty consisting of the introduction of regularity, a law between cause and effect. Zeno identified this regularity with providence as corporeal intelligence (logos) in the cosmic fire (pyr technikon or pyr noetikon) located within the world and governing it. This theory reflected that of the soul of the universe developed by Plato. The soul appeared to be ordering and performing a providential function in the universe.53 The major difference from Plato’s scheme was that in Zeno’s system the order was to be periodically destroyed and renewed according to a cyclic rhythm. Chance (tēchē) was, for the Stoics, another word for a situation where the causes are not clearly visible, known, or differentiated.54

Among causes, the Stoics differentiated between two types: external causes attributed to the working of fate and internal causes related to the particular nature and linked to necessity (anankē).55 Moreover, determinism was the effect brought about jointly by these two sets of causes. Additionally, “living things possess a natural movement, and this is a movement in accordance with impulse (hormē).”56

A more detailed description of the forces operating in the living organism was given by Origen:

But of these [creatures] which have the cause of their movement within themselves, some are said to be moved out of themselves, others within themselves; and they are so divided because those which have life but no soul move out of themselves, those which have soul from within themselves. These latter move when there comes to them an image, that is a kind of desire or incitement, which impels them to move towards an object. Again, there exists in certain animals such an image, that is, a desire or feeling, which by a natural instinct impels and excites them to ordered and complex motion; as we see in spiders, which by an image, that is, desire and longing to weave a web, are excited to accomplish in an orderly manner the work of weaving, some natural movement undoubtedly calling forth the impulse to do this kind of work; nor do we find that this insect has any other feeling beyond the natural longing to weave a web. So too, the bee is impelled to fashion honeycombs and to gather, as they call it, aerial honey. But while the rational animal has in itself these natural movements, it has also, to a greater extent than the other animals, the faculty of reason, by means of which it can judge (krinō) and discern between the natural movements, disapproving of and rejecting some and approving of and accepting others. So by the judgment of this reason the movements of men may be guided and directed towards an approvable life.57

Living creatures operate driven by impulse which is generated from sensory presentation. In some animals the transition is automatic, but in humans the impulse is to be produced in a controlled manner due to the operation of the judging power—the reason (logos). Man is the only creature endowed with the capacity to understand cosmic events and to promote the rationality of Nature. He also is the only being that has the capacity to act in a manner that fails to accord with the operation of Nature [call it a Kantian freedom] and as such he is a moral agent. Man has “impulses to virtue” or “seeds of knowledge” as tools for his actions, and this is sufficient to direct reason in the right direction.58

5. Cicero and His Formulation of the Natural Law

Thus in the Stoic philosophy humans have a natural capacity to act in accordance with the natural law or “right reason” through the impulse to virtue. We find this understanding of the natural law formulated by Cicero59 in his Republic:

True law is right reason in agreement with nature; it is of universal application, unchanging and everlasting; it summons to duty by its commands, and averts from wrongdoing by its prohibitions. And it does not lay its commands or prohibitions upon good men in vain, though neither has any effect on the wicked. It is a sin to try to alter this law, nor is it allowable to attempt to repeal any part of it, and it is impossible to abolish it entirely. We cannot be freed from its obligations by senate or people, and we need not look outside ourselves for an expounder or interpreter of it. And there will not be different laws at Rome and at Athens, or different laws now and in the future, but one eternal and unchangeable law will be valid for all nations and all times, and there will be one master and ruler, that is God, over us all, for he is the author of this law, its promulgator, and its enforcing judge. Whoever is disobedient is fleeing from himself and denying his human nature, and by reason of this very fact he will suffer the worst penalties, even if he escapes what is commonly considered punishment…60

Cicero in the Laws explains why this natural law is called law by differentiating understanding of it by the “populace” and by the “learned men”:

Well then, the most learned men have determined to begin with Law, and it would seem that they are right, if, according to their definition, Law is the highest reason, implanted by Nature, which commands what ought to be done and forbids the opposite. This reason, when firmly fixed and fully developed in the human mind, is Law. And so they believed that Law is intelligence, whose natural function it is to command right conduct and forbid wrongdoing. They think that this quality derived its name in Greek from the idea of granting to every man his own, and in our language I believe it has been named from the idea of choosing. For as they have attributed the idea of fairness to the word law, so we have given it that of selection, though both ideas properly belong to Law. Now, if this is correct as I think it to be in general, then the origin of Justice is to be found in Law, for law is a natural force; it is the mind and reason of the intelligent man, the standard by which Justice and Injustice are measured. But since our whole discussion has to do with the reasoning of the populace, it will sometimes be necessary to speak in the popular manner, and give the name of law to that which in written form decrees whatever it wishes, either by command or prohibition. For such is the crowd’s definition of law. But in determining what Justice is, let us begin with that supreme Law which had its origin ages before any written law existed and or any State had been established.61

It is clear that Cicero defines natural law as “law” by analogy to the human positive law, and such is its popular understanding. However, in reality it is natural force – mind and reason inherent in human nature regardless of the underlying and accepted metaphysics – recognized by “the most learned men” that directs our behavior on an individual and social level. It is natural because it is proper for human nature:

that animal which we call man, endowed with foresight and quick intelligence, complex, keen, possessing memory, full of reason and prudence, has been given a certain distinguished status by the supreme God who created him; for he is the only one among so many different kinds and varieties of living beings who has a share in reason and thought, while all the rest are deprived of it.

And further:

But those who have reason in common must also have right reason in common. And since right reason is law, we must believe that men have Law also in common with gods. Further, those who share Law must also share Justice.62

6. Natural Development of Human Rationality

Thus in the Stoic view, natural law is a function of our human reason which, however, can be corrupted, and which functions both for an individual and for the society. Stoics could not have said much about the biological conditioning of our behavior except to say that Nature works by allowing a stepwise development of rationality, as the development of an individual proceeds, and with it the moral awareness through the mechanism of an “impulse” (hormē):

An animal’s first impulse, say the Stoics, is to self preservation, because Nature from the outset endears it to itself, as Chrysippus affirms in the first book of his work On Ends when his words are, ‘The dearest thing to every animal is its own constitution thereof,’ for it was not likely that Nature should estrange the living thing from itself or that she would leave the creature she has made without either estrangement from or affection for its own constitution. We are forced then to conclude that Nature in constituting the animal made it near and dear to itself; for so it comes to repel all that is injurious and give free access to all that is serviceable or akin to it. As for the assertion made by some people that pleasure is the object to which the first [primary] impulse of animals is directed, it is shown by the Stoics to be false. For pleasure if it is really felt, they declare to be a by-product, which never comes until Nature by itself has sought and found the means suitable to the animal’s experience or constitution; it is an aftermath comparable to the condition of animals thriving and plants attaining full bloom. And Nature, they say, made no difference originally between plants and animals, for she regulates the life of plants too, in their case without impulse and sensation just as also certain processes go on as a vegetative kind in us. But when in the case of animals impulse has been superseded, whereby they are enabled to go in quest of their proper aliment, for then, say the Stoics, Nature’s role is to follow the direction of impulse. But when reason by way of a more perfect leadership has been bestowed on the beings we call rational, for them life according to reason rightly becomes the natural life. For reason supervenes as the craftsman of impulse.63

The first natural impulse of a living creature, e.g. of a child, is directed not towards the outside world, but towards itself; it becomes self-aware and develops an “affection” for itself. This statement about primary impulse is an empirical one and the logical starting-point for Stoic ethics. Self-preservation (searching for food, defense against enemies, procreation) would be the only natural and right thing to follow if humans did not have the faculty of reason. 64

Therefore, the pattern of human behavior changes from a purely animal-like instinctive pattern to a fully rational one and involves, according to Cicero, five stages. They represent the development of human nature, but only a few people will reach its highest stages because the process is not independent of a man’s own effort. The “function” or goal of man in this process is attainment of perfection of his nature. The term used by Cicero is officium (corresponding to the English office, duty or task, as the office of an official charged with certain duties) and the Greek term is kathēkon (appropriate action). One could not speak about the “duty” of an animal or of an infant but rather of their natural function. The term duty becomes appropriate in stages three through five in human development as the changes in behavior become now functions of a rational being. Similar views on human moral development were formulated by Lawrence Kohlberg65 and Kazimierz Dąbrowski.66

These psychological studies can be correlated with the studies of physical development of brain by Magnetic Resonance Imaging (MRI) and Graph Theory, a mathematical method allowing to measure how different brain regions develop and interconnect allowing correlation between changes in brain development and changes in behavior and cognition.67

Medieval Interpretation of the Natural Law and Morality

Thomas Aquinas, the most prominent Christian philosopher and a great mind, constructed a comprehensive system of moral philosophy including the concept of the natural moral law.

His starting point was the Aristotelian conception of happiness or moral wellbeing [eudaimonía]68 as the ultimate end of human living.69 He supplemented this concept with religious doctrine: “the human mind’s final perfection is by coming to union with God.”70 Our actions as human actions are rational and voluntary, and depend on our choice. Following Origen, Aquinas states that only such free acts based on the will in view of an end and apprehended by reason can be classified as moral actions, good or bad (“acts are called human inasmuch as they proceed from deliberate will” and “moral acts and human acts are the same”).71

Aquinas’entire theory of justification of morals is an analogy, developed by comparison with the model of positive human law and the legal system. He postulated five laws: 1. The ETERNAL LAW – the deity himself:

a law is nothing else but a dictate of practical reason emanating from the ruler who governs a perfect community. Now it is evident, granted that the world is ruled by Divine Providence, as was stated … that the whole community of the universe is governed by Divine Reason. Wherefore the very Idea of the government of things in God the Ruler of the universe, has the nature of a law. And since the Divine Reason’s conception of things is not subject to time but is eternal…, therefore it is that this kind of law must be called eternal;

2. The positive DIVINE LAW, which is two-fold: the Old Divine Law, imperfect, underdeveloped, of the Old Testament, and the New Divine Law, fully developed, of the New Testament; 3. NATURAL LAW (“lex naturalis” or sometimes called “lex naturae“):

law, being a rule and measure, can be in a person in two ways: in one way, as in him that rules and measures; in another way, as in that which is ruled and measured, since a thing is ruled and measured, in so far as it partakes of the rule or measure. Wherefore, since all things subject to Divine providence are ruled and measured by the eternal law, as was stated above… it is evident that all things partake somewhat of the eternal law, in so far as, namely, from its being imprinted on them, they derive their respective inclinations to their proper acts and ends. Now among all others, the rational creature is subject to Divine providence in the most excellent way, in so far as it partakes of a share of providence, by being provident both for itself and for others. Wherefore it has a share of the Eternal Reason, whereby it has a natural inclination to its proper act and end: and this participation of the eternal law in the rational creature is called the natural law… thus implying that the light of natural reason, whereby we discern what is good and what is evil, which is the function of the natural law, is nothing else than an imprint on us of the Divine light. It is therefore evident that the natural law is nothing else than the rational creature’s participation of the eternal law… Even irrational animals partake in their own way of the Eternal Reason, just as the rational creature does. But because the rational creature partakes thereof in an intellectual and rational manner, therefore the participation of the eternal law in the rational creature is properly called a law, since a law is something pertaining to reason, as stated above… Irrational creatures, however, do not partake thereof in a rational manner, wherefore there is no participation of the eternal law in them, except by way of similitude;


a law is a dictate of the practical reason. Now it is to be observed that the same procedure takes place in the practical and in the speculative reason… Accordingly we conclude that just as, in the speculative reason, from naturally known indemonstrable principles, we draw the conclusions of the various sciences, the knowledge of which is not imparted to us by nature, but acquired by the efforts of reason, so too it is from the precepts of the natural law, as from general and indemonstrable principles, that the human reason needs to proceed to the more particular determination of certain matters. These particular determinations, devised by human reason, are called human laws, provided the other essential conditions of law be observed, as stated above … that ‘justice has its source in nature; thence certain things came into custom by reason of their utility; afterwards these things which emanated from nature and were approved by custom, were sanctioned by fear and reverence for the law. … The human reason cannot have a full participation of the dictate of the Divine Reason, but according to its own mode, and imperfectly. Consequently, as on the part of the speculative reason, by a natural participation of Divine Wisdom, there is in us the knowledge of certain general principles, but not proper knowledge of each single truth, such as that contained in the Divine Wisdom; so too, on the part of the practical reason, man has a natural participation of the eternal law, according to certain general principles, but not as regards the particular determinations of individual cases, which are, however, contained in the eternal law. Hence the need for human reason to proceed further to sanction them by law. … The practical reason is concerned with practical matters, which are singular and contingent: but not with necessary things, with which the speculative reason is concerned. Wherefore human laws cannot have that inerrancy that belongs to the demonstrated conclusions of sciences. Nor is it necessary for every measure to be altogether unerring and certain, but according as it is possible in its own particular genus;

and 5. The bizarre “LAW OF SIN” (“lex peccati“) or the LAW OF FOMES:

Accordingly under the Divine Lawgiver various creatures have various natural inclinations, … a law for one, is against the law for another. … And so the law of man, which, by the Divine ordinance, is allotted to him, according to his proper natural condition, is that he should act in accordance with reason: and this law was so effective in the primitive state, that nothing either beside or against reason could take man unawares. But when man turned his back on God, he fell under the influence of his sensual impulses: in fact this happens to each one individually, the more he deviates from the path of reason, so that, after a fashion, he is likened to the beasts that are led by the impulse of sensuality… So, then, this very inclination of sensuality which is called the ‘fomes,’ in other animals has simply the nature of a law (yet only in so far as a law may be said to be in such things), by reason of a direct inclination. But in man, it has not the nature of law in this way, rather is it a deviation from the law of reason. But since, by the just sentence of God, man is destitute of original justice, and his reason bereft of its vigor, this impulse of sensuality, whereby he is led, in so far as it is a penalty following from the Divine law depriving man of his proper dignity, has the nature of a law.72

The basis for Natural Law is the religious scheme of reality, the human condition, and the governance of the world by God. What Aquinas calls the “Natural Law” is the partici­pation of the rational creature in the Eternal Reason through which it has its own natural aptitude for its due activity and purpose. It includes, however, the principles governing nonrational creatures as well. Following the Stoics and Cicero, Aquinas states that this participation is natural for humans because humans have a rational nature:

Whatever is contrary to the order of reason is contrary to the nature of human beings as such; and what is reasonable is in accordance with human nature as such.73

Thus the Natural Law is “an ordinance of reason for the common good” and “the rule and measure of acts, whereby man is induced to act or is restrained from acting.”74 However, Aquinas goes beyond Cicero by postulating that the light of natural reason by which we discern what is good and evil is the impression of the divine light on us. He describes Natural Law further as the first principles of human moral activity that are self-evident, indemonstrable (“sunt quaedam principia per se nota”), and known to all. The first command of law is “that good is to be sought and done, evil to be avoided;” and on this command “are founded all the other precepts of the law of nature.”75 The commandments of the Natural Law are recognized by practical reason as being a human good (“quae ratio practica naturali­ter apprehendit esse bona humana”). According to Aquinas, the order of natural commandments corresponds to our natural tendencies or inclinations.76

Thus, the behavior of nonrational creatures too is governed similarly but not recognized as a law, because only humans are able to recognize and formulate such precepts. Nevertheless, that Aquinas admits that these animals participate in them classifies their behavior as natural inclinations and instincts. Aquinas was not familiar with evolutionary processes in the world, i.e. with the evolution of living organisms and humans. He put very rigid barriers between inanimate, animate, and human worlds. He did not recognize the continuity of forms and substances in the universe. The term “instinct” used by Aquinas in a rigid sense as behavior governed by inflexible rules has no longer an application today to animals in evolutionary terms.

Aquinas next argues that since our activity of reason and will derives from what we are by nature and since all reasoning originates from principles which we recognize naturally as well as the desire for objectives that are subordinate to ends it is only proper that our acts should be primarily directed towards this ultimate end by the Natural Law.77 Therefore, natural is what is preconscious, predetermined, self-evident, and not reasoned out. On the other hand he seems to accept the definition of Ulpian that what is the natural is what we have in common with animals, or what is “instinctive” or intuitive, according to the definition of Gratian:78

the precepts of the natural law are to the practical reason, what the first principles of demonstrations are to the speculative reason; because both are self-evident principles. … Consequently the first principle of practical reason is one founded on the notion of good, viz. that ‘good is that which all things seek after.’ Hence this is the first precept of law that ‘good is to be done and pursued, and evil is to be avoided.’ All other precepts of the natural law are based upon this: so that whatever the practical reason naturally apprehends as man’s good (or evil) belongs to the precepts of the natural law as something to be done or avoided. Since, however, good has the nature of an end, and evil, the nature of a contrary, hence it is that all those things to which man has a natural inclination, are naturally apprehended by reason as being good, and consequently as objects of pursuit, and their contraries as evil, and objects of avoidance. Wherefore according to the order of natural inclinations, is the order of the precepts of the natural law. Because in man there is first of all an inclination to good in accordance with the nature which he has in common with all substances: inasmuch as every substance seeks the preservation of its own being, according to its nature: and by reason of this inclination, whatever is a means of preserving human life, and of warding off its obstacles, belongs to the natural law. Secondly, there is in man an inclination to things that pertain to him more specially, according to that nature which he has in common with other animals: and in virtue of this inclination, those things are said to belong to the natural law, ‘which nature has taught to all animals,’79 such as sexual intercourse, education of offspring and so forth. Thirdly, there is in man an inclination to good, according to the nature of his reason, which nature is proper to him: thus man has a natural inclination to know the truth about God, and to live in society: and in this respect, whatever pertains to this inclination belongs to the natural law; for instance, to shun ignorance, to avoid offending those among whom one has to live, and other such things regarding the above inclination.80

Only later do we recognize these natural tendencies as laws, precisely because we are rational creatures. Even nonrational creatures participate in Eternal Reason in their own way; how­ever, they cannot perceive it as a law. When referring to them, we may use the word “law” only in a figurative manner. Because of the double nature of humans (rational and animal), some acts of virtue follow Natural Law as they belong to it by the fact that our proper form is the soul. Therefore, our natural tendency is to act according to virtue. Many virtues, however, do not belong to Natural Law but are reasoned out before they are held helpful to the good life: for example, temperance modulates our natural desire for food, drink, and sex. Sins, if they are against reason, are against nature. On the other hand, some special sins run against nature, such as homosexuality, which, as Thomas thought, is against the course natural to all animals.

With this is associated the issue of changeability of the Natural Law which was introduced first by Aristotle. Aquinas recognized that moral conclusions arrived at by human reason can vary. He solved this problem by postulating two types of principles belonging to the Natural Law. He maintains that the first common principles of theoretical or practical reason, “the law of nature,” are the same as the truth or rightness for all and are equally recognized. With respect to the specific conclusions of theoretical reason, the truth is the same for all, though not all recognize it equally. With respect to the particular conclusions derived by practical reason, there is no general unanimity as to what is true or right, and even when there is agreement there is not the same degree of recognition. In a few cases, the desire to do right or information may be wanting.

Thus, according to Aquinas, Natural Law with its first principles is a spontaneous, intuitive, “instinctive” reflex of tendency to seek what is good, to preserve natural being, to preserve the species, and to learn about God and venerate him. This “law” has supernatural origin having being created together with human nature and is self-evident. Practical reason next arrives at the common principles of the Natural Law, which may differ in details and in specific conclusions. However, he postulates one most general principle of practical reason quoting it in Gratian’s formulation.81 This principle is supplanted from the Judaic and Greek traditions into Christianity, but is found in all cultures and religions.82 He summarizes what is a natural right by quoting Gratian that it is that “by which everyone is commanded to do to others what he would have done to himself, and forbidden to do to others what he would not have done to himself.”83 And it is generally held that all human inclinations should be directed according to reason.

The first principles of the law of nature (“lex naturae”) are altogether unalterable. But its secondary precepts, which are like particular conclusions close

to the first principles, though not alterable in the majority of cases where they are right as they stand, can nevertheless be changed on some particular and rare occasion.

Now expanding the scope of Natural Law, Aquinas uses the notion of Natural Law in a double meaning – a narrow one as the very first principle or principles we recognize unconsciously, and the second, in the broader meaning that includes also particular conclusions derived from it in society.

Aquinas’ concept of morality is very restricted and applies only to those rational beings who are able to consciously formulate these rules of behavior. This version of moral behavior found its secular parallel in Kant’s categorical imperative which has a character of a law and operates strictly in humans, and hypothetical imperative operating on the principles of feelings, impulses, and inclinations, and thus can be applied to higher animals as well. Moreover, in Kant’s thinking the moral sense or obligation, whether in its absolute form or in the hypothetical imperative is inherent in humans and not originated by participation in divine reason. Modern science finds that higher animals behave similarly to humans with similar feelings, impulses, and inclinations that have developed by the evolutionary process of socialization. This leads to a refinement of our understanding of moral behavior by contemplating its correlation with the evolution of higher animals. Aquinas, as restricted as he was by his religious notions, nevertheless, recognized that even nonrational higher animals might follow rules of behavior similar or identical to humans though they are not able to recognize them as laws. Modern theologians and religious scholars attempt to explain traditional theological speculations and biblical stories using the language and concepts of evolutionary biology.84

Foundation of Kant’s Moral Philosophy and its Reinterpretation

Kant’s writings on ethics85 are the most important since antiquity. Kant argues, following the ancient Stoics, that our moral obligations in a final analysis derive from reason by recognition of the natural moral law, and not from either god, or communities, nor from inclinations or desires. But being a practical realist, Kant differentiates several levels of motivation and rules of the behavior that preserve human autonomy and free choice in moral decisions. Thus his theory, just as its sources (Aristotle’s psychology and the Stoic doctrine), is deeply humanistic.

There are many parallels in Kant’s thought with the ideas developed by the ancient Stoics and Eastern traditions developed in Indian culture and in China. His thought is thus an elaboration of the themes of ancient philosophers.86 It is important for our analysis to keep in mind that the philosophical intuitions we find in various schools in the West and in the East can be reevaluated today in a more precise way due to the progress in the natural sciences, and especially from the evolutionary perspective. This is not to say that such perspectives were absent in previous searches, especially in the ancient Greek or Indian thought. The naturalistic outlook represented in the ancient schools and the philosophical intuition are confirmed today by studies of our biological nature. Yet we humans are not automata which follow the prescribed pattern of input/output operating in the mechanical, even highly adaptive systems, defined by science. With the rise of sentient and rational life appeared a new quality in nature, namely, freedom.87 Still this freedom should be controlled by reason, though we are not always motivated by moral law. Today, modern science provides insight into the mechanisms operating in human behavior at several levels.

1. Condition of Morality

Kant begins his treatise Foundations of the Metaphysics of Morals (1785)88 with the classification of our rational knowledge. Kant specified the task of a moral philosopher as: 1. one of clarifying the “principle of morality” on which the rational agent can act insofar as his action is morally good; 2. to justify this principle, that is, to show that this principle is actually binding upon an imperfect agent such as a human being; 3. to apply this principle to build an exposition of human obligations, i.e., duties. In this first work out of the three treatises devoted to moral philosophy,89 Kant dealt with the first task of the moral philosopher. He was not interested in constructing an ethical doctrine or writing a casuistry of morals but rather searched for an axiom or principle that might be used for building a general theory of laws of freedom (in contrast to the laws of nature, concerned with physical nature), the science of which he called ethics or theory of morals. In the Metaphysics of Morals (1797), Kant defined more precisely what ethics is; namely the science of how one is under obligation without regard for any possible external lawgiving, that is, as doctrine of virtue.90 Just as natural philosophy (physics) has its empirical part so does moral philosophy because it must determine the human will as it is affected by nature. Kant calls this anthropology.

The laws of moral philosophy are therefore those according to which everything should happen, allowing for conditions under which what should happen often does not. Though the title of Kant’s work contains the word “metaphysics,” it is not about the understanding of ultimate reality, or the metaphysics of nature, but rather a rigorous search for the establishment of a supreme principle of a possible pure will which cannot be derived from observations of actual behavior of men but by reason. For Kant defines metaphysics as “a system of a priori knowledge from concepts alone … a practical philosophy, which has not nature but freedom of choice for its object,” and as such it requires a metaphysics of morals which “every man also has it within himself, though as a rule only in an obscure way.”91

Kant begins his considerations with an analysis of the conditions for attaining happiness – namely, of being worthy to be happy, i.e., of having a good will that strives for moral perfection. Our moral obligation in the Greek and Judaic traditions is to achieve this “purity of heart” or “kingdom of god,” which means good will. “Nothing in the world – indeed nothing even beyond the world – can possibly be conceived which could be called good without qualification except a good will.”92 This statement represents a spontaneous respect for moral law and an innate sense of “ought.” It is an empirical postulate derived from observation of universal human nature. Kant next analyzes in quite an evolutionary approach that nature for achieving its end – preservation of life and its welfare – selects instinct rather than reason:

For all the actions which the creature has to perform with this intention, and the entire rule of conduct, would be dictated much more exactly by instinct, and that the end would be far more certainly attained by instinct than it ever could be by reason. And if, … reason should have been granted to the favored creature, it would have served only to let it contemplate the happy constitution of its nature, to admire it, to rejoice in it, and to be grateful for it to its beneficent cause. But reason would not have been given in order that the being should subject its faculty of desire to that weak and delusive guidance and to meddle with the purpose of nature. In a word, nature would have taken care that reason did not break forth into practical use nor have the presumption, with its weak insights, to think out for itself the plan of happiness and the means of attaining it. Nature would have taken over not only the choice of ends but also that of the means, and with wise foresight she would have entrusted both to instinct alone… Reason is not, however, competent to guide the will safely with regard to its object and the satisfaction of all our needs … and to this end an innate instinct would have led with far more certainty. But reason is given to us as a practical faculty, i.e., one which is meant to have an influence on the will. As nature has elsewhere distributed capacities suitable to the functions they are to perform, reason’s proper function must be to produce a will good in itself and not one good merely as a means, for to the former reason is absolutely essential.93

The function of reason is thus the establishment of this “good will.” Good will is good because of its willingness; that is, it is good in itself without regard to anything else. It is not the sole and complete good but rather the highest good and the condition for all others. “It dwells already in the natural sound understanding and does not need so much to be taught as only to be brought to light. In the estimation of the total worth of our actions it always takes first place and is the condition of everything else.”94 As an example of such situation Kant gives us an interpretation of the scriptural passages that command us to love neighbors and enemies. It is not done from inclination but duty, which resides in the will and not in feelings or propensities, but in principles of action.

Kant here is describing nothing other than common moral consciousness and from it derives principle for moral action. Charles Darwin observed that in the time of Kant the origin of this moral consciousness was questioned and Kant himself wondered about it. Darwin was among the first who gave a naturalistic explanation for its origin. He stated in his The Descent of Man (1871):95

I fully subscribe to the judgment of those writers who maintain that of all the differences between man and the lower animals, the moral sense or conscience is by far the most important. This sense as Mackintosh96 remarks, ‘has a rightful supremacy over every other principle of human action;’ it is summed up in that short but imperious word ought, leading him without a moment’s of hesitation to risk his life for that of a fellow-creature; or after due deliberation, impelled simply by the deep feeling of right or duty, to sacrifice it in some great cause. Immanuel Kant exclaims, ‘Duty! Wondrous thought, that workest neither by fond insinuation, flattery, nor by any threat, but merely by holding up thy naked law in the soul, and so extorting for thyself always reverence, if not always obedience; before whom all appetites are dumb, however secretly they rebel; whence thy original?’97

This great question has been discussed by many writers of consummate ability; and my sole excuse for touching on it, is the impossibility of here passing it over; and because, as far as I know, no one has approached it exclusively from the side of natural history. The investigation possesses, also some independent interest, as an attempt to see how far the study of the lower animals throws light on one of the highest physical faculties of man.

The following proposition seems to me in a high degree probable – namely, that any animal whatever, endowed with well-marked social instincts, the parental and filial affection being here included, would inevitably acquire a moral sense or conscience, as soon as its intellectual powers have become as well, or nearly as well developed as in man.

We can now add that modern science confirms Kant’s intuition and provides a biological, naturalistic, and evolutionary explanation for the existence of this moral consciousness.

Kant insists that in deciding what we ought to do our variable desires are not important – for an action to be truly moral it has to be done in the belief and because of the belief that it is right, i.e., out of respect for moral law.

It is important to indicate at this point that Kant and all philosophers until Darwin considered as truly (strictly) moral the actions produced by conscious rational and reflective analysis. This view arose from Origen’s account of the Stoic analysis of the motion of objects and action of animals and humans.98 Origen reported that the Stoics differentiated human beings from all other natural things by a particular kind of movement (action) unique to them. What distinguished them from others was that they are had a certain kind of cause (aitía) of motion in themselves. Things like plants and animals have an internal cause of motion, “nature” (logos for Stoics) and “soul” (in Origen’s view); inanimate objects must have an external agency to be moved along; and are moved by thrust of external force. Plants and animals by virtue of having “soul” (and “nature”) are capable of self-movement or action. In the case of animals, sensory stimulation is a necessary condition of the impulse to self-movement. Those lacking intelligence move and act according to a prescribed pattern. Human beings do not move or act in a set fashion—because the faculty of reason (logos) enables them to judge (krinō) their sensory presentations, to reject or accept, and to be guided. Origen calls this third kind of movement (action) self-movement of which only rational animals are capable, motion (action) “through themselves.”99 We are deserving of praise when we choose the noble and avoid the base, but when we follow the opposite course we are blameworthy. Origen reasoned:

It is neither true nor reasonable to lay the blame on external things and release ourselves from the accusation making ourselves analogous to wood and stones inasmuch as they are drawn along by external things that move them; such is the argument of someone who wants to set up a counterfeit notion of autonomy. For if we should ask him what autonomy is, he would say that it obtains ‘if there are no external causes, when I intend to do something in particular, that incite to the contrary.’100

The Stoics believed that human beings are capable of self-movement without actually initiating their own motion. Origen’s account of the difference in motion (action) between humans and other animals gave rise to the concept of morality as a behavior conditioned by a rational, reflective act. Origen said:

We must not forget, however, that the greater part of the nature assigned to every rational creature is in animals in varying degree, some having more and some less; so that the instinct in hunting dogs and in war horses comes near, if I may say so, to reason itself. To be subject, then, to particular external impression which gives rise to such or such image is admittedly not one of the things lying within our power; but to decide to use what has happened either in this way or in that is the work of nothing else but the reason within us, which, as the alternatives appear, either influences us towards the impulses that incite to what is good and seemly or else turns us aside to the reverse.101

Many actions, even if they produce good results, that are done in accordance with the law do not belong to the realm of moral actions in this strict sense if they are done with some ulterior motives. Thus truly morally good action is not only in accord with the law but also because the law is acknowledged as absolutely and universally binding. Kant formulated the condition of morality with three propositions: 1. It must be done from duty; 2. Moral value is in the maxim by which action is determined, thus it depends on the principle of volition; 3. Duty is a necessity of an action from the respect of law, i.e., consciousness of the submission of the will to a law. Moreover, the subjective principle of volition must be distinguished from the objective principle of volition which would serve all rational beings also subjectively if they were governed by reason.

2. Moral Law or Categorical Imperative

Kant next derives the concept of moral law from consideration of pure reason and will. Everything in nature works according to laws, but only a rational being has the capacity of acting according to the conception of laws, i.e., according to principles.

This conception of law derives from Stoic philosophy as a natural capacity to act in accordance with “right reason” through the impulse to virtue. We find such a formulation of the “natural law” in Cicero’s Republic.102

Cicero in the Laws explained why this natural law is called law by differentiating understanding of it by the “populace” and by the “learned men;” and at the same time he explains the etymology of the term “law” from the idea of “choosing” and fairness implied by the term.103

It is clear that Cicero defines natural law as “law” by analogy to the human positive law, and such is its popular understanding. However, in reality it is natural force, mind and reason inherent in human nature regardless of the underlying and accepted metaphysics, recognized by “the most learned men” that directs our behavior on an individual and social level. It is natural because it is proper for human nature.104

Kant equates this capacity to act according to the conception of laws with will. But since reason is required for the derivation of actions from laws, will is nothing else but the practical reason that governs human behavior through a conception of law. In human beings, however, reason by itself does not sufficiently determine the will, which is also subjugated to subjective conditions not always agreeing with objective ones. But the pure conceptions of duty and moral law have the highest influence. Kant emphasizes that moral theory that is put together from a mixture of incentives, feelings, inclinations and partially from rational concepts makes the mind vacillate between motives and leads only accidentally to good and often to bad. The conception of an objective principle governing our actions is a command of reason and the formulation of it is an imperative, an expression containing an “ought.”

If an action is good as a means to something else, the imperative is hypothetical, and thus is conditional upon circumstances and advisable only. Such a goal cannot be universally held by all men at all times. Further, hypothetical imperatives can be divided into those that are technical (imperative of skill), those that belong to art, and those that are pragmatic (imperative of prudence), belonging to welfare of the being.

Accordingly, Kant differentiated three levels of behavioral rules operating in the living world:

1. The instinctive rules to which belong human urges satisfying our physiological and biological needs, as well as behavior of lower social animals. They are controlled by genes or epigenetic rules.

2. The heteronomous rules (hypothetical imperative, where the action is a means to something else or the will is subjected to extraneous motivations) which Kant divided into two types. A. One type, empirical, is associated with desires, fear, and other motivations. Here belong also the rules produced by the so-called moral sense which is responsible for subconscious or vaguely perceived, non-reflective actions and reactions. They may operate as well in higher animals. Modern science enlarges this intuition of Kant indicating that there is a subconscious, quasi-instinctive component in human behavior which may be controlled genetically and/or a result of habituation.105Also behavior of higher animals like apes may be controlled by this unconscious mechanism. It cannot be termed “moral,” however, using the Kantian definition of morality (morality in the strict sense). Once these rules are consciously recognized, they constitute the basis for moral reflective behavior (morality in the strict sense). Nevertheless, higher animals have a certain subconscious recognition of rules of behavior common with humans which we prefer to classify as proto-morality. B. The second type, rational, refers to heteronomous rules which are produced by reflection; however, they are motivated by extrinsic values such as achieving perfection or theological considerations.

3. The autonomous rules (categorical imperative), which are attained by conscious reflection representing the categorical imperative. These are moral rules in the fullest sense of morality proper only to humans.

Modern Psychological and Philosophical Studies on the Development of Human Morality

This classification of behavioral levels derives from Stoic doctrine106 and corresponds to the stages of moral development of man through which community life and virtue are recognized as pre-eminently “things belonging to man” in their terminology and are related to autonomous behavior (categorical imperative of Kant). In modern times, Kazimierz Dabrowski107 (1902-1980) and Lawrence Kohlberg108 (1927-1987) confirmed the Stoic view of man’s moral development. Dabrowski developed a theory of positive disintegration which views psychic breakdown as an important step to personality building. This disintegration embraces a variety of processes of emotional disturbance or even complete breakdown. But he considers them natural processes for integration, psychic health, adaptation to the environment, and building of personality. Kohlberg, following the studies of Jean Piaget109 (1896-1980), suggested six stages of moral development of children and adults through three levels – the pre-conventional, conventional, and post-conventional, each subdivided into two stages. The first two levels correspond to the heteronomous behavioral level of Kant. Level 1: stage 1 – morality is understood as obedience, punishment, and avoidance of harm to others; stage 2 – morality is understood as satisfying one’s own interests and letting others do the same; Level 2: stage 3 – morality is understood as playing the role of being a good person, i.e., meeting expectations, following the rules, and being concerned for others (generally defined as group identification); stage 4 – morality is understood as doing one’s duty, maintaining the social order and the welfare of the society. This stage is generally defined as recognition of authority. In the third level (Level 3) in stage 5, morality is understood as the basic rights, values, and legal contracts of a society. Positive laws and duties are calculated on overall utility (utilitarian morality). This stage involves critical thinking and choice; in stage 6 morality is understood as an accord with universal, self-chosen principles (e.g., justice, equality, and respect for the dignity of all human beings) which confer validity to maxims and actions. This level involves internalization of the principle of autonomy and corresponds completely to the autonomous behavioral level (categorical imperative) in Kant’s classification. This is the level where human internal dialogue elevates moral behavior to a level of abstraction and self-reflection absent until humans entered the evolutionary scene.

Jürgen Habermas Adopts the Kantian Moral Philosophy Model

The Kantian pattern of moral behavior was adopted by Jürgen Habermas (b. 1929), a popular contemporary German philosopher-sociologist, with only a small modification.110 Habermas develops Kantian ethics into a discourse of social consensus. Habermas considers modernity as a process by which subjects liberate themselves from traditional roles and values, to create a new social order through communication and discourse, a new “normativity.” And he understands this “normativity” as new meanings and understandings that are shared and rational, i.e., based on mutual recognition of validity claims. The issue here is the emergence of secular morality from the Judeo-Christian tradition, namely the question of how to live one’s life. Habermas contends that gradually a normative ethics as an exposition of detailed norms based on religious tradition was replaced by competing conceptions of the good and transformed from a set of commands to a system of principles and valid norms which are universal and unconditional. Though they are a legacy of the religious tradition, these norms function in a new social order. Such a consideration refers to the existing morality in practice.

Similarly, one could consider the history of a moral theory, and Habermas emphasizes that Kant was the first among moral philosophers who pointed to the modern conception of morality, namely, the “formula of the universal law,” maxims which are incorporated into the will: “Act only on that maxim by which you can at the same time will it to be a universal law.” In Kant’s ethics, moral actions are expressions of a free act and based on establishing the validity of moral norms by each individual. Habermas, as a sociologist, criticizes Kant for this individualistic twist and considers morality a collective process of reaching a consensus: “The emphasis shifts from what each can will without contradiction to be a general law, to what all can will in agreement to be a universal law.” But this critique is not justified; he simply overlooked Kant’s principle of universality at the same time he contradicts himself by introducing “moral discourse” which is equivalent to the Kant theory of morals and concerns norms which are absolute and are either unconditionally valid or invalid and hold across competing cultural traditions. They are evaluated either as right or wrong, just or unjust, and are deontological, their validity unconditional. But the detailed rules of behavior conditioned by social situations are labeled by Habermas as “ethical discourse,” and he claims that in many situations it is difficult to separate these two discourses. Habermas, nevertheless insists on the priority of moral discourse and moral norms to always trump ethical values, confirming Kant’s theory of the moral. This is due to the fact that in this discourse values are removed from the justification process: moral norms are not cultural values but they are communicative ideals of universal validity, and moral discourse is not rooted in any particular cultural tradition but belongs to the post-conventional level of the understanding of morality.

Categorical imperatives are possible because the idea of freedom makes man a member of the intelligible world. If one were a member only of this intelligible world, then all actions would be in accordance with the autonomy of the will. But since man is at the same time a member of the world of sense, his actions ought to conform to the autonomy of the will as belonging to the intelligible world, which, according to reason, should dominate the sensuously affected will. Anyone who is accustomed to using reason is conscious of the good will that constitutes the law for his bad will as a member of the world of sense and acknowledges the authority of this law even while transgressing it. The moral “ought” is one’s own volition as a member of the intelligible world. It is conceived as an “ought” only insofar as one regards himself at the same time as a member of the world of sense.

Kant next asserts, however, that philosophy has no knowledge of this supersensible world; it only can indicate its possibility and thus philosophy defends the foundations of morality.

Modern Science Provides a Biological Foundation for Human Moral Behavior

As we have seen, the Stoics claimed that the pattern of human behavior changes from purely animal-like and instinctive to fully rational and involves five stages. They represent the development of human nature, but only a few people will reach the highest stages because the process is not independent of a man’s own effort. Thus the Stoics recognized a natural biological basis for human behavior from which reason draws conclusions, develops rules, and constructs a moral philosophy.111 Even Kant wondered about the origin of the moral principle that humans display and which he called “goodwill.”112

The “function” or goal of man in this process is attainment of the perfection of his nature. The term used by Cicero officium (duty or task, as the in the office of an official charged with certain duties) could not be applied to an animal or an infant, so one could not talk about the “duty” of an animal or of an infant but rather of their natural function. The term duty becomes appropriate in stages three-through-six in Kolberg’s model of human development as the changes in behavior become the functions of a rational being.113

Evolutionary Biology and Cooperation

Looking at the principles of evolutionary theory, it seems at first that the existence of cooperation should be contradictory to the evolutionary process. Darwin noticed this difficulty already when he discussed the origin of social moral faculties in “the primeval man.” Darwin admitted that such traits as courage and fidelity could increase in competition between tribes: “A tribe rich in the above qualities would spread and be victorious over other tribes.”114 But asking how a large number of members could become endowed with these social and moral qualities within the same tribe, Darwin answered himself:

He who was ready to sacrifice his life, as many a savage has been, rather than betray his comrades, would often leave no offspring to inherit his noble nature. … Therefore it hardly seem probable, that the number of men gifted with such virtues, or that the standard of their excellence could be increased through natural selection, that is by the survival of the fittest; for we are not speaking here of one tribe being victorious over another.115

Darwin postulated that though the high standard of morality may give a slight advantage to each individual in a tribe, yet an increase in the number of well-endowed men and an advancement in the standard of morality more generally will certainly give an immense advantage to one tribe over another. A tribe that includes many members who, from possessing in a high degree the spirit of patriotism, fidelity obedience, courage, and sympathy, were always ready to aid one another and to sacrifice themselves for the common good would be victorious over most tribes, and this would be natural selection.”116 Evolutionary scientists classify this as a “between-group selection.” Moreover, cooperative and altruistic behavior, understood not in the everyday sense of conscious act but as a behavior which benefits other organisms at a cost to the donor, is widely shared throughout the animal kingdom.117 It seems from the studies of many biologists that entire organisms like multicellular organisms with specialized cells could also be considered as made up of cooperating cells, and entire colonies of social organisms depend on cooperation and often altruistic sacrifice of some individuals for the sake of the group.118 Thus, Martin A. Nowak who builds mathematical models for evolution considers cooperation its third fundamental process after mutations and natural selection.119 The problem puzzled many biologists, economists, and mathematicians. Darwin suggested that natural selection favored families whose members were cooperative and answered Kant’s question about the origin of moral rule.120

Such predictions by Darwin are confirmed today by scientific investigations that postulate the existence of cooperative behavior in the animal world. Scientists have developed several behavioral models using computer modeling and studies of animals.121 Most recently, Frans de Waal122 summarized studies on the primate behavior suggesting that we share our human behavioral traits with higher primates and that our morality, as predicted by Darwin and many philosophers, is a refinement of basic fundamental processes operating in nature.

Modern Science enlarged the Kantian paradigm of behavioral rules into three levels of morality understood in a broad sense (Table 1).

Table 1

Three Levels of Morality Compared From Animal Studies

Level Description Humans and Apes Compared

1. Moral sentiments Human psychology provides In these areas, there exist (Kant’s instinctive behavior) “building blocks” of morality, evident parallels with

such as the capacity for empathy, other primates.

a tendency for reciprocity, a sense

of fairness, and the ability to

harmonize relationships.

2. Social pressure Insisting that everyone behaves in Community concern and

(Kant’s heteronomous a way that favors a cooperative prescriptive social rules

behavior) group life. do exist in other primates,

The tools to this end are reward, but social pressure is less

punishment, and reputation systematic and less building. concerned with the goals of society as a whole.

3. Judgment and reasoning Internalization of others’ needs and Others’ needs and

(Kant’s autonomous goals to the degree that these goals may be behavior) needs and goals figure in internalized to

our judgment of behavior some degree, but including others’ behavior we do not know that does not directly touch us. this since we Moral judgment is self-reflective are not able to (i.e., governs our own behavior communicate with as well) and often logically reasoned. other species.

According to Frans de Waal, (with modifications), Primates and Philosophers (Princeton and Oxford: Princeton University Press, 2006), p. 168.


Such studies and others led to the formulation of humanity capacity for moral judgment and action as a “moral faculty.”123 This concept of the “moral faculty” or rather “moral capacity” goes back to antiquity when the ancients had a premonition of innate moral principles (moral sentiment, sense of justice, common moral thought), which were working subconsciously.124 It is the basis for the moral rules which like rules of logic or of natural sciences are objective truths, outcomes of rational choice.

These rules were developed and formulated in various cultures with varying degree of success, and today they are at the foundation of humanistic ethics. John Rawls (1921-2002) in his well known treatise A Theory of Justice (1971) suggested that these innate moral principles can be analogized to the “sense of grammaticality” (a “faculty of grammar”) described by Noam Chomsky.125 (Table 2).

Table 2


Characteristics of the moral faculty (capacity) derived from the principle of fairness postulated by Rawls.


  1. Analogous to the faculty of language: from a limited experience comes out a broad range of utterances; from limited set of moral experiences we project intuition to novel cases. Generalization process could be the same for language mathematics, categorization of objects, morality, etc.

  2. Moral judgments emerge rapidly without reflection, emotions, and without clear justification or explanation. They are robust and firm. No conscious reasoning is involved here, we know by intuition how to behave. Even having conscious access to some moral principles underlying our moral behavior may have as little impact or none on our moral behavior as knowing the principles of language has on our speaking. (Knowledge comes from a subconscious intuition).

  3. Moral conflicts are resolved by considered judgment uniting the subconscious principles with expressed principles: they are rapid, automatic, without reflection, without emotion, and without awareness of specific moral rules or principles. Once such judgments are formed, they are subject to different constraints, revisions, refinement, and rejection.

  4. Unconscious principles imbedded in the moral faculty are the original position, e.g., how to evaluate dispensation of compensation for individual actions in the contractarian model of Thomas Hobbes, in the self-interest model of Adam Smith where the individual self-interests promote the public interest, or in the justice model of Rawls where they operate under the veil of ignorance or impartiality, i.e., free of knowledge of anyone’s age, wealth, religious beliefs, health, ethnicity, or other biases.

Finally, a few words should be devoted to the so-called altruistic behavior of animals as contrasted with the so-called selfish behavior. These two terms have different meanings in biological studies of behavior. In popular usage, however, the term selfish is used to mean self-centered behavior. In biology this term means self-serving behavior without motives or intentions implied by “selfish.” One cannot say about a spider building a web that he is doing this intentionally for his self-centered interest to catch flies. It seems that insects do not have a capability to predict the results of their actions. So similarly, the term “altruistic behavior” signifies a behavior benefiting the recipient without regard to motives or intentions. Humans behave altruistically most often spontaneously, automatically, and instinctively without previous rationalization, though we are able to act altruistically after cognitive reflection. Primates behave the same way, and we cannot expect that they always plan this behavior anticipating a reward. Thus de Waal differentiated several levels of altruistic behavior: 1. Functional, done without any appreciation of cost or benefit; 2. Socially motivated – a result of distress of others or begging; 3. Intentional – done with awareness how others may benefit (limited to humans and a few large-brained animals); 4. “Selfish” helping – done with expectation of returned benefits.

Table 3

Classification of Altruistic Behavior

Functionally Socially Motivated Intentionally Targeted “Selfish”

Altruistic helping helping helping

Cost to performer, Empathic response Awareness of how the Intentionally

benefit to recipient to distress or begging other will benefit seeking return benefit

Most animals

 Many social animals

 Humans, some large-brained animals

Humans, some large-brained animals

Frans de Waal, Primates and Philosophers. How Morality Evolved (Princeton and Oxford: Princeton University Press, 2006), p. 180.


We may now present a brief exposition of how the natural law should be understood so far. The natural law postulate formulates recognition of a general principle operating in nature which is innate in humans and governs their behavior. It has a character of law because it is binding to humans; it is universal, because it is independent of particular human positive law and applies to all people. Our human understanding of this natural law grows with the development of our rationality; thus, it is a law of human nature, a law of reason. Our behavior changes from an animal-like instinctive pattern to a fully rational one through stages: “The first appropriate function of a creature is to maintain itself, in its natural condition. The second, that it should seize hold of the things which accord with Nature and banish those which are the opposite.” Thus we can differentiate in the natural law two types of principles – one instinctive, automatic which directs our behavior unconsciously, and the second one, reflective, rational at which we arrive after some analysis. For as soon as man acquires the capacity for understanding or conceptual reasoning, he draws rational conclusions that the highest human good is that which is worthy of praise and desirable for its own sake.126

These principles are classified as law from popular understanding of governing principles in analogy to written laws, that is human positive law which “in written form decrees whatever is it wishes, either by command or prohibition.” But in reality “law is intelligence, whose natural function it is to command right conduct and forbid wrongdoing… it is the mind and reason of the intelligent man, the standard by which justice and injustice are measured.”

Christian religious thinkers adopted the Ciceronian formulation of the natural law, for Thomas Aquinas stated that reason is the rule and measure of human action: “The good of the human being is being in accordance with reason, and human evil is being outside the order of reasonableness… So human virtue, which makes good both the human person and his works, is in accordance with human nature just in so far as it is in accordance with reason; and vice is contrary to human nature just in so far as it is contrary to the order of reasonableness.”127 It was linked, however, to their religious speculations.

Following Darwin, primatologists and other biologists128 have long argued that the roots of human morality are manifest in social animals like apes and monkeys. These species express feelings of empathy, expectations of reciprocity and fairness, community concerns, and gratitude, which are essential behaviors for mammalian group life and constitute a counterpart to human morality. Marc D. Hauser, summarizing all studies done with animals and in modern psychology and anthropology, proposes that people are born with a capacity for moral judgment (moral grammar of Rawls) wired into their neural circuits by evolution. This grammar generates instant moral judgments which are instantaneously inaccessible to the conscious mind. Hauser presents his argument as a hypothesis to be proved, but it has solid experimental grounding, including work with primates and young children and in empirical results derived from studies performed by moral philosophers. Hauser argues that moral grammar operates in much the same way as the universal grammar proposed by linguist Noam Chomsky for developing language faculty. This universal grammar is a system of rules for generating syntax and vocabulary but does not specify any particular language. That is supplied by the culture in which a child grows up. By analogy, moral grammar, too, is a system composed of neural circuits which generate moral behavior and not a list of specific rules. Basic rules are the same in every society, but cultural variations are allowed, since cultures can put different emphases on its elements.

This proposal has strong and far-reaching implications. It suggests that parents and teachers do not really teach children the rules of correct behavior; rather, they instill cultural biases and modifications. Also, it demonstrates in a tangible way that religions are not the source of moral codes. On the contrary, moral grammar which operates subconsciously is immune to religious doctrines. At best, religions enforce instinctive behavior, and it seems that they developed for the purpose of enforcing the internalization of rationally recognized “building blocks” of morality: capacity for empathy, tendency for reciprocity, and a sense of fairness.129 Moral grammar is a product of the evolutionary process because restraints on behavior are necessary for social living and have been favored by natural selection for survival. Friedrich Nietzsche was among those philosophers who argued for societal origin of rules of behavior which developed as cultures evolved.130

Moral grammar, now universal among people, is thought to have evolved to its present shape during the hunter-gatherer stage of our past, some 50,000 years ago, through the mechanism of group selection as was suggested already by Nietzsche in a cultural context.

The question now arises, what validity does moral philosophical speculation have in view of scientific theories and the evidence behind them, such as the one postulated by Hauser? The answer which is suggested by Hauser was presented in the form of three models for human behavior incorporating three major themes of philosophical speculation.

The first model, the so-called Humean Model, is based on the entire line of philosophical speculation going back in antiquity to the Stoics, and in modern times has been best expressed by David Hume. Hume assumed that “perceptions” produce feelings and emotional reactions from which follows judgment.

The second model, labeled the Kantian Model, emerges from Kant’s moral philosophy as a misunderstanding or single-minded interpretation of his “categorical imperative.” Hauser, who noticed this misconception, introduced a double path in the model. Kant accepted the existence of something he called “good will.” It has thus a quality of an instinct. We proceed to evaluate events, actions, etc., either on some principles which he classified as: 1. Heteronomous (empirical e.g., from principle of happiness, the so-called moral sense, inclinations, etc. or rational e.g., from the concept of perfection, (transcendental or theological) because they derive from the outside of the individual; 2. An autonomous or categorical imperative which is an autonomous moral law, a law for the will of every rational being. He expressed it as a formula or maxim by which we can judge. It has to be universal to be classified as the moral imperative.

But Kant did not go, and in his time it would be very difficult to do so, into the biological foundations of this mechanism. It was anyway an ideal situation if all humans behaved all the time in such a rational way. He knew that humans do not behave all the time in this way and do not always use reason for judgment. Thus these heteronomous principles were valid in practice (and still are).

The third model, the Rawlsian Model, is based on the theory of John Rawls who postulated an instinctive “moral faculty” that allows us to differentiate moral actions and situations from those which have no moral value and to differentiate actions which are allowed, permissible, or forbidden. So in this last model we have perception first, then automatically (unconsciously) we judge them and only then we develop emotions and feelings about them. Of course in the later stage comes also conscious reflection and reasoning which is then the basis for developing cultural rules, laws, etc. The last model is more realistic and it accommodates all previous models as certain approximations while at the same time is confirmed by evidence from scientific studies in many disciplines and provides evolutionary basis for human behavior. Still Kant’s model seems to be the most complete though its biological basis could not be developed in his time.

1 Joseph Campbell, The Masks of God: Occidental Mythology, (Penguin Books: Harmondsworth, U.K.; New York, USA, 1976). Joseph Campbell, The Masks of God: Oriental Mythology, (Penguin Books: Harmondsworth, U.K.; New York, USA, 1986). W.Y. Evans-Wentz, compiler and editor, The Tibetan Book of the Dead, (Oxford University Press: Oxford, UK, 1960). The Texts of Taoism, translated by Jmaes Legge, Part I, II, (Dover Publications, Inc. : New York, first published, 1962). James B. Pritchard, ed., The Ancient Near East. Anthology of Texts and Pictures, Vol. 1, 2, (Princeton University Press: Princeton, 1973). Hindu Myths. A Sourcebook Trasnalted from the Sanskrit. With introduction by Wendy Doniger O’Flaherty, (Harmondsworth, UK: Penquin Books, 1975). The Rig Veda, translated and annotated by Wendy Doniger O’Flaherty, (Harmondsworth, UK: Penquin Books, 1984). The Upanishads, translated by F. Max Müller, Part 1, 2, (Dover Publications: New York, first published 1962). Sarvepalli Radhakrishnan, Indian Philosophy, Vol. 1, 2 (first publication, George Allen and Unwin Ltd, 1931). James P. Allen, translator and introduction, The Ancient Egyptian Pyramid Texts, (Society of Biblical Literature: Atlanta, GA, 2005). Wing-Tsit Chan, translated and compiled, Ssource Book in Chinese Philosophy, (Princeton University Press: Princeton, 1963). Hammurabi, The Oldest Code of Law in the World. The Code of Law Promulgated by Hammurabi, King of Babylon B.C. 2285-2242 (Hard Press, 2006). W.W. Davies, The Codes of Hammurabi and Moses with Copious Comments and, Index, and Bible References (Book Jungle, 2007).

2 Leonard Swidler, “Toward a Universal Declaration of a Global Ethic,” in Dialogue and Humanism, The Universalist Journal, Vol. IV, No. 4, 1994, pp. 51-64.

3 Russ Shafer Landau, The Fundamentals of Ethics, (New York, Oxford: Oxford University Press, 2010). Henry Sidgwick, The Methods of Ethics (London: Macmillan and Co., 1901; first edition 1877).

4 R. Paul Thompson, “An Evolutionary Account of Evil.” In Michael Ruse, ed., Philosophy after Darwin. Classic and Contemporary Readings (Princeton and Oxford: Princeton University Press, 2009). Pp. 533-538.

5 Herbert Lionel Adolphus Hart, Law, Liberty and Morality (Stanford: Stanford University Press, 1963). Adam Krokiewicz, Moralność Homera i Etyka Hezjoda (Warszawa: Instytyut Wydawniczy PAX, 1959). Adam Krokiewicz, Etyka Demokryta i Hedonizm Arystyda (Warszawa: Instytut Wydawniczy PAX, 1960).

6Heraclitus, The Cosmic Fragments. Edited with an introduction and commentary by G. S. Kirk (Cambridge: Cambridge University Press, 1954). fr. 114.

7Hesiod, The Homeric Hymns and Homerica, with an English translation and by Hugh G. Evelyn-White (Cambridge, MA: Harvard University Press, 1982), pp. 276-284.

8Jürgen Habermas, contemporary German philosopher calls this age an Axial Age.

9 The words Sophist (sophistes) derives from the Greek sophos (skilled, wise, clever, learned, subtle, ingenious), sophia (skill, cleverness, wisdom, learning), sophizomai (practice an art, play tricks, devise skillfully, speculate). The term was widely used in the ancient Greece and designated a poet, as a teacher of men, a knowledgeable and prudent man, a person with a specific skill, expert or adept. In the fifth century this term acquired a specific meaning designating a class of Sophists i.e. of professional teachers, educators, scholars who gave lessons in grammar, rhetoric, politics, mathematics, for money. They taught in small seminars or circles, in public gatherings or private homes. This term became an abusive term in the hands of the satirical writer, Aristophanes, who slandered them and criticized as deceivers. For him Sophists represented an age of decline and breakdown of morals. Athenians were ambivalent about Sophists for they claimed to teach aretē (virtue) and how to become a good citizen (Plato, Protagoras 319a). Athenians in their democratic outlook did not consider that a special training was necessary for this in contrast to learning specific practical skills (technē). Their opinion was shared by Plato who named them “worthless fellows” primarily for their atheism or agnosticism. In the next century Aeschinus referred to Socrates as “Socrates the sophist” and later Lucian of Samosata (125-180) referred to Christ “that crucified sophist” (Peregrinus 13). W. K. C. Guthrie, The Sophists, Cambridge UK: Cambridge University Press, 1971, reprint of 1987 edition), pp. 35-54. The texts of preserved fragments of the Sophists’ writings are available in a bilingual collection: Sofisti. Testimonianze e frammenti. Testo greco a fronte. A cura di Mario Untersteiner con la collaborazione di Antonio Battegazzore. Introduzione di Giovanni Reale, indici di Vincenzo Cicero, (Milano: Bompiani, 2009).

10Modern evaluation of the Sophists indicates that they were not the source of decline in Greek thought, as Plato thought, but on the contrary they represented a transitional period in moral and intellectual development leading to the period of great philosophies of Plato, Aristotle, the Stoics, Epicurus and others.

11The most prominent among Sophists one can list: Protagoras of Abdera (490-420 B.C.E.), Gorgias of Leontinti (485-380 B.C.E.), Hippias of Elis (ca 460-ca 390), Antiphon of Athens (480-411 B.C.E), Prodicus of Ceos (465-395).

12For example Antiphon in Jan Legowicz, Filozofia Starożytna Grecji i Rzymu (Warszawa: Państwowe Wydawnictwo Naukowe, 1968), p. 123-124.

13Plato, The Republic, Parmenides, in The Republic and Other Works, translated by B. Jowett, (New York: Anchor Book, 1973). Plato, Complete Works. Edited with Introduction and Notes, by John M. Cooper. Associate Editor D.S. Hutchinson (Indianapolis/Cambridge: Hachett Publishing Company, 1997).

14Famous dialogue from Euthyphro : “Euthyphro – Yes, I should say that what all the gods love is pious and holy, and the opposite which they all hate, impious. Socrates – Ought we to inquire into the truth of this, Euthyphro, or simply to accept the mere statement on our own authority and that of others? Euthyphro – We should inquire; and I believe that the statement will stand the test of inquiry. Socrates – That, my good friend, we shall know better in a little while. The point which I should first wish to understand is whether the pious or holy is beloved by the gods because it is holy, or holy because it is beloved by the gods.” Plato, Euthyphro in The Republic and Other Works, op. cit., p. 435.

15Aristotle, Nicomachean Ethics, translated, with introduction and notes by Martin Ostwald, (New York, London: Macmillan Publishing Company, 1962), Bk V. 7.

16Aristotle, Nichomachean Ethics, op. cit., Bk I.7.

17 Lawrence C. Becker, A New Stoicism (Princeton, NJ: Princeton University Press, 1998).

18It was founded by Zeno of Citium (333-262 B.C.E.) and developed by his successors Cleanthes (303-233 B.C.E.) and Chrysippus (b. ca 280 -d. ca 208/4 B.C.E.). Stoicorum Veterum Fragmenta collegit Ioannes Ab Arnim (Stutgardiae: in Aedibus B.G. Teubneri, MCMLXIV), Vol. 1-4, (abbreviated as SVF). Italian edition with translation of the Fragmenta: Gli Stoici. Opere e Testimonianze a cura di Margherita Isnardi Parente, Vol. 1-2. (Milano: TEA, 1994). A. A. Long, Hellenistic Philosophy. Stoics, Epicureans, Sceptics (Berkeley: University of California Press, 1986), second edition.

19SVF, II. 945.

20SVF, II. 67.

21 Marcus Aurelius, Meditations, translated by Gregory Hayes (NewYork : Modern Library,

2002), II.1.

22Marcus Aurelius, op. cit., V.16.

23Jürgen Habermas, Moral Consciousness and Communicative Action, translated by Christian Lenhardt and Shierry Weber Nicholsen (Cambridge, Mass: The MIT Press, 1990). Immanuel Kant Foundations of the Metaphysics of Morals and What is Enlightenment? Translated with an introduction by Lewis White Beck (New York: Macmillan Publishing Company, twenty-first printing 1988).

24 Lucius Annaeus Seneca, Epistulae morales ad Lucilium (Las Vegas : CreateSpace, Independent Publishing Platform, 2014), Ep. 65, 12-15.

25Marcus Tullius Cicero, On Fate (De fato) & The Consolation of Philosophy: IV 5-7,V Boethius. Edited with introduction, translation and commentaries by R. W. Sharples (Warminster: Aris & Phillips, 1991). 39-44.

26 SVF, II. 1000.

27Aristotle, Περι ψυχχης, Traité de l’âme (De anima), traduit et annoté par G. Rodier, III, 10-11.

28SVF, II. 984. “Being free to act otherwise” is the paradigmatic statement of the concept of free will adopted by the Christian thinkers.

29SVF, II. 991.

30Diogenes Laertius (abbreviated later as D.L.), Lives of Eminent Philosophers with an English translation by R. D. Hicks (Cambridge, MA: Harvard University Press, 1995). Vol 1-2. VII. 89; SVF III. 229-236.

31Plutarch, De Stoicorum repugnantiis, in Plutarchi Chaeronensis Moralia (Athens : Akademia Atheniensis, Institutum Litterarum Graecarum et Latinarum Studiis Destinatum, 2008), p. 32-37.

32SVF II. 1118.

33Zeno and Chrysippus defined the goal of man as “to live in accordance with experience of natural events.” SVF I, 179; III. 5.

34Edward O. Wilson, Consilience. The Unity of Knowledge (New York: Alfred A Knopf, 1998). Marc D. Hauser, Moral Minds. How Nature Designed Our Universal Sense of Right and Wrong (New York: HarperCollins Publishers, 2006).

35Jürgen Habermas, Between facts and Norms, translated by William Rehg (Cambridge, MA: Polity Press, 1998), p. 311.

36D.L. VII. 156

37SVF, II. 714-716.

38D.L. VII. 59.

39SVF, III. 377.

40SVF, II. 171.

41SVF, II. 979, 991.

42Aëtius, IV. 11.4 in Dox. graeci. op. cit.; Sénèque Lettres à Lucillius Texte établi par François Préchac et traduit par Henri Noblot (Paris: Société d’Édition “Les Belles Lettres,” 1964),. Tome I-VII. T. V. Ep. 124.9.

43D.L. VII. 86.

44Cicero, De natura deorum, op. cit., II, 29; Sénèque, Lettres à Lucillius, op. cit., T. V. Ep. 121, 10.

45Cicero, Du bien suprême et des maux les plus graves (De Finibus) traduction nouvelle avec notice and notes par Charles Appuhn (Paris: Librairie Garnier Frères, 1938). III, 20. Cicero, On Moral Ends, edited by Julia Annas, translated by Raphael Woolf (Cambridge, UK: Cambridhge University Press, 2007), III.20.

46Epictetus, Discourse and Enchiridion based on translation of Thomas Wentworth Higginson with an introduction by Irwin Edman (Roslyn, N.Y.: Walther J. Black, 1944) I.6.19-20.

47SVF ,II. 899; III. 5, 175, 438, 466, 488.

48SVF ,I. 203; III. 468.

49SVF, III. 175, 570-571.

50SVF, III. 459.

51 SVF III. 278.

52SVF II. 912, 915-917, 937, 943, 945, 975-976.

53Plato Laws, in Complete Works, X. 896d-897c.

54SVF II. 965, 966, 970, 973.

55SVF II. 979, 974.

56SVF II.979.

57SVF II.988. Origen (185-ca 254), church father, succeeded Clement of Alexandria in the school of Alexandria. The patriarch of Alexandria who at first supported Origen expelled him later for being ordained without the patriarch’s permission. Origen then moved to Palestine and died there. He wrote commentaries on all the books of the Bible. In a treaise First Principles (Peri Archon) he formulated the philosophical exposition of Christian doctrine in which he interpreted scripture allegorically. He was a Neo-Pythagorean, and Neo-Platonist and like Plotinus believed that the soul passes through stages of incarnation before reaching God. For him even demons would be reunited with God. He considered God the First Principle, and Christ, the Logos, the secondary principle who was subordinate to him. Origen’s views were declared anathema in the VIth century. Origen, On the First Principles, translated by G.W. Butterworth, with introduction by Henri de Lubac (New Yoek: Harper & Row Publishers, 1973), Bk. III, I. 2-3, p. 159.

58SVF I. 566.

59 Marcus Tullius Cicero (106 B.C.E.-46 B.C.E.) was a Roman politician, lawyer, philosopher, and linguist, one of the greatest minds on the ancient Rome. Cicero introduced to the Romans knowledge of the Greek schools of philosophy and created Latin philosophical language. His voluminous writings were influential in the subsequent centuries for developing political and legal thought, and especially Christian ethical thought. His philosophy, Stoic in its outlook, is humanist and still serves as a starting point for modern religious and secular elaborations. Among the most cited works of Cicero one must list On the Nature of the Gods (De natura deorum), On the Chief Good and Evil (De finibus bonorum et malorum), On Fate (De fato), On Laws (De legibus), and On Duties (De officiis).

60 Cicero, The Republic, in De re publica. De legibus, with an English translation by Clinton Walker Keyes (Cambridge, MA; London: Harvard University Press, William Heinemann, Ltd, 1988). Bk III. XXII.

61 The Greek term for law is nomos, which Cicero derives from nemō, to distribute, to grant, and the Latin term lex Cicero drives from lego, to choose. Quote from The laws, in De re publica. De legibus, op. cit., Bk I.VI.18-19.

62Cicero, The Laws, in op. cit., Bk I.VII.22-23.

63Diogenes Laertius Lives of Eminent Philosophers with an English translation by R. D. Hicks (Cambridge, MA: Harvard University Press, 1995). Vol 1-2. VII. 85-86.

64Cicero, De Finibus, III. 20-21.

65 Lawrence Kohlberg (1927-1987) developed a theory, based on the philosophical intuition of Cicero, of the moral development of children through three levels – the pre-conventional, conventional, and post-conventional, each subdivided into two stages: level 1: stage 1 – morality is understood as obedience and punishment and avoidance of harm to others; stage 2 – morality is understood as satisfying one’s own interests and letting others do the same; level 2: stage 3 – morality is understood as playing the role of being a good person, i.e., meeting expectations, following the rules, and being concerned for others; stage 4 – morality is understood as doing one’s duty, maintaining the social order and the welfare of the society. Level 3: stage 5 – morality is understood as basic rights, values, and legal contracts of a society. Laws and duties are calculated on overall utility (utilitarian morality); stage 6 – morality is understood as an accord with universal, self-chosen principles (e.g., justice, equality and respect for the dignity of all human beings) which confer validity to maxims and actions (Kantian morality).

66 Kazimierz Dabrowski, Positive Disintegration, edited, with an introduction, by Jason Aronson (Boston: Little, Brown and Company, 1964). Kazimierz Dabrowski, Personality Shaping through Positive Disintegration, introduction by O. Hobart Mowrer (London: J. & A. Churchill Ltd., 1967).

67 Neuroscientific studies show progressive maturation of various regions of the brain by increase in connectivity among brain regions as evidenced by increasing volume of white matter; that is the level of myelin wrapping up around the axons. Myelination taking place from childhood to adulthood speeds up the conduction of nerve impulses up to 100 times. It also allows a quicker recovery time, an increase up to 30 times in frequency with which neurons can transmit information. Another effect produced by myelination is strengthening the synapses or connections allowing for neurons to fire at a certain electrical threshold and coordinate better the activities in different parts of the brain on a variety of cognitive tasks. This interconnectivity can now be measured by applying Graph Theory, a mathematical method. Graph Theory allows one to measure how different brain regions develop and interconnect and allow correlation between changes in brain development and changes in behavior and cognition. Brain circuits develop from the stage of an embryo and continue throughout life. The amount of gray matter consisting of neuron cell bodies, dendrites and certain axons, increases during childhood, reaches its maximum around age of puberty and starts declining through adolescence plateauing during adulthood and starts declining again in senescence. The same pattern applies to the density of receptors on neurons. However, its development in terms of myelination of axons and strengthening of synapses occurs at different times in different parts of the brain. It matures faster in the primary sensorimotor areas devoted to sensing and responding to sight, sound, smell, taste, and touch. Gray matter matures latest in the prefrontal cortex which is important in development of our cognition, development of executive functions such as organization, decision making, formulation of hypotheses, planning, regulation of emotions, and of our social cognition: ability to form and analyze social relationships, discern friends from foes, etc. Jay N. Giedd, The Amazing Teen Brain, in Scientific American, July 2015, Vol. 312, No. 6, pp. 33-37.

68  English text of Aristotle’s Nichomachean Ethics, in The basic Works of Aristotle,edited and with introduction by Richard McKeon (New York: Random House, 1941).

69 The text of Aquinas’s “Summa Theologiae” is that published in Latin-English version by Blackfria­rs in con­jun­ction with Mc­Gr­aw-Hill Book Co­mpany, New York, and Eyre & Spott­is­woode, London, 1963-1972. Summa Theologiae, 1a 2ae, 1,7; Ibidem, 1a 2ae, 90,2.

70 Ibidem, 1a 2ae, 3,8.

71Ibidem, 1a 2ae, 1,3.

72 Summa Theologiae, 1a 2ae, 91. 1,2,3,4,5,6.

73Ibidem, 1a 2ae, 71. a.2e.

74 Ibidem, 1a 2ae, 90. a.1.4.

75Ibidem, 1a 2ae, 94.2.

76 Ibidem, 1a 2ae, 94.2.

77 Ibidem, 1a 2ae, 91.2.

78Ulpian (murdered in 223 C.E.) and Gaius (ca 110 – ca 180) were Roman jurisconsults (“jurisperiti”) who set in order Roman law. Roman law was systematized by Emperor Justin­ian in “Digest” (“Digesta,” 533 C.E.), Institutes (Institutiones, 533), and Justinian’s Code (Codex Justinianus, 528, 534). These were supplemented by additional decrees accumulated over the years as Novellae (Novels). Roman law was adapted to the politics of state and church. Ulpian and Gaius introduced the definition of “natural law” in terms of what we share in common with animals. Gratian published in 1141 a miscellany of texts related to legislation of the Western church entitled “Decretum” which became the canon law of the church and the state. Decretum I, 1,7: “Ius naturale est commune omnium nationum, eo quod ubique instinctu naturae, non constitutione aliqua habetur“. In Corpus Iuris Canonici, editio Lipsiensis secunda post Aemilii Ludovici Richteri curas ad librorum manu scriptorum et editionis Romanae fidem recognouit et adnotatione critica instruxit Aemilius Friedberg. Graz: Akademische Druck U. Verlagsanst­alt, 1959.

79 Reference to Ulpian; see note 78.

80Ibidem, 1a 2ae, 94,2.

81 Summa Theologiae, 1a 2ae, 94.4. “Consequently we must say that the natural law, as to general principles, is the same for all, both as to rectitude and as to knowledge. But as to certain matters of detail, which are conclusions, as it were, of those general principles, it is the same for all in the majority of cases, both as to rectitude and as to knowledge; and yet in some few cases it may fail, both as to rectitude, by reason of certain obstacles (just as natures subject to generation and corruption fail in some few cases on account of some obstacle), and as to knowledge, since in some the reason is perverted by passion, or evil habit, or an evil disposition of nature; thus formerly, theft, although it is expressly contrary to the natural law, was not considered wrong among the Germans, as Julius Caesar relates (De Bello Gall. vi)… The meaning of the sentence quoted is not that whatever is contained in the Law and the Gospel belongs to the natural law, since they contain many things that are above nature; but that whatever belongs to the natural law is fully contained in them. Wherefore Gratian, after saying that ‘the natural law is what is contained in the Law and the Gospel,’ adds at once, by way of example, ‘by which everyone is commanded to do to others as he would be done by.’

82  Leonard Swidler, “Toward a Universal Declaration of a Global Ethic,” in Dialogue and Humanism, The Universalist Journal, Vol. IV, No. 4, 1994, pp. 51-64. Michael Shermer, The Science of Good and Evil (New York: Times Books/Henry Holt and Company, 2004), p. 25-26.

83Gratian, op. cit., Decretum I,1: “Ius naturae est, quod in lege et euangelio continetur, quo quisque iubetur alii facere, quod sibi uult fieri, et prohibetur alii inferre, quod sibi nolit fieri.”

84 Craig A. Boyd, “Thomistic Natural Law and the Limits of Evolutunary Psychology.” In Michael Ruse, ed., Philosophy after Darwin (Princeton and Oxford: Princeton University Press, 2009), pp. 522 -532. R. Paul Thompson, “An Evolutionary Account of Evil,” in ibidem, pp. 533-539.

85 Foundations of the Metaphysics of Morals (1785), Critique of Practical Reason (1788), Metaphysics of Ethics (1797).

86 The ancient moral philosophy of the Stoics is till valid. It acquired in Kant’s elaboration more precise generalization. But this philosophy still inspires more detailed elaborations and application to modern conditions of life, especially by combining the concepts developed by Kant with general outlook of the Stoics. Such an approach reached the level of a new height of logical analysis in the work of Lawrence C. Becker, A New Stoicism (Princeton, NJ: Princeton University Press, 1998).

87Daniel C. Bennett, Freedom Evolves (New York: Viking, 2003). Gregory R.Peterson, “Falling Up: Evolution of Original Sin.” In Michael Ruse, ed., Philosophy after Darwin (Princeton and Oxford: Princeton University Press, 2009), pp. 539-548.

88 Immanuel Kant, Foundations of the Metaphysics of Morals and What is Enlightenment? Translated, with Introduction, by Lewis White Beck (New York: London: Macmillan Publishing Company, Collier Macmillan Publishers, 1988). Onora O’Neill, “Kantian Ethics.” In A Companion to Ethics. Peter Singer, ed. (Oxford: Blackwell Publishers, 1997), pp. 175-185.

89 Those three treatises are: the Foundations of the Metaphysics of Morals (1785), Critique of Practical Reason (1788), and Metaphysics of Morals (1797).

90 Kant, Metaphysics of Morals, introduction, translation, and notes by Mary Gregor, (Cambridge; Cambridge University Press, 1991), XVII, 410.

91 Ibidem, II, 216.

92 Kant, Foundations, op. cit., p. 9.

93 Kant, ibid. p. 11-12.

94 Kant, ibid. p. 15.

95 Charles Darwin, The Descent of Man, in The Origin of Species and The Descent of Man (New York: The Modern Library, no date). Chapter 4, pp. 471-472.

96 Mackintosh, Dissertation on Ethical Philosophy, 1837, p. 231.

97 Immanuel Kant, Metaphysics of Ethics, translated by J .W. Semple (Edinburgh, 1836), p. 136. This quote comes from Kant’s work Critique of Practical Reason (1788). The full quote is: “Duty! Thou sublime and mighty name that dost embrace nothing charming or insinuating but requirest submission and yet seekest not to move the will by thretening aught that would arouse natural aversion or terror, but only holdest forth a law which of itself finds entrance into the mind and yet gains reluctant reverence (though not always obedience) – a law before which all inclinations are mute even though secretly work against it: what origin is worthy of thee, and where is the root of thy noble descent which proudly rejects all kinship with the inclinations and from which to be descended is the indispensable condition of the only worth which men alone can give themselves?” Immanuel Kant, Critique of Practical Reason, edited and translated with notes and introduction by Lewis White Beck, third edition (New York: Macmillan Publishing Company, 1993), p. 90.

98 See note 57.

99Stoicorum Veterum Fragmenta Collegit Ioannes Ab Arnim (Stutgardiae: In Aedibus B.G. Teubneri, MCMLXIV). Vol 1-4. (abbreviated as SVF). SVF II.989, 879. Origen, De principiis, (On the First Principles), translted with introduction and notes by G. W. Butterworth (Gloucester, Mass.: Peter Smith, 1973). III, 1, 2, 3.

100SVF II.990.

101Origen, op. cit., Bk III, 3, p. 160. SVF II.992.

102 Cicero, The Republic, in De re publica. De legibus, with an English translation by Clinton Walker Keyes (Cambridge, MA; London: Harvard University Press, William Heinemann, Ltd, 1988). Bk III. XXII.

103 The Greek term for law is nomoi which Cicero derives from nemō, to distribute, to grant, and the Latin term lex Cicero derives from lego, to choose. Quote is from The laws, in De re publica. De legibus, op. cit., Bk I.VI.18-19.

104 Cicero, The Laws, in op. cit., Bk I.VII.22-23.

105 This aspect of human behavior was amply discussed and elaborated by the Stoics. In modern times Friedrich Nietzsche was one of the early philosophers who recognized the importance of social pressures on a society for the development of moral rules. Friedrich Nietzsche, The Birth of Tragedy and The Genealogy of Morals, translated by Francis Golfing, (New York: Anchor Books, 1990).

106SVF 1.197.

107 Kazimierz Dabrowski, Positive Disintegration, edited, with an introduction, by Jason Aronson (Boston: Little, Brown and Company, 1964). Kazimierz Dabrowski, Personality-shaping Through Positive Disintegration, introduction by O. Hobart Mowrer (London: J. & A.Churchill, Ltd, 1967).

108 Lawrence Kohlberg, Essays on Moral Development, (San Francisco: Harper & Row, 1981, 1984), Vols. 1, 2.

109 Jean Piaget, The Moral Judgment of the Child, translated by Marjorie Gabain (New York: The Free Press, A Division of Mamillan Publishing Co., 1965). Ronald Duska and Mariellen Whelan, Moral Development. A Guide to Piaget and Kohlberg (New York, Paramus, Toronto: Paulist Press, 1975). Emile Durkheim, Moral Education. A study in the Theory and Application of the Sociology of Education, forward by Paul Fauconnet, translated by Everett K. Wilson and Herman Schnurer, edited, with a new introduction, by Everett K. Wilson (London: The Free Press, A Division of Macmillan Publishing Co., 1973).

110Jürgen Habermas, Moral Consciousness and Communicative Action, translated by Christian Lenhardt and Shierry Weber Nicholsen (Cambridge, Mass: The MIT Press, 1990 [1983]).

111 Marian Hillar, “Natural Development, Rationlity, and Responsibility in Stoic Ethics,” published in the Essays in the Philosophy of Humanism, Robert D. Finch, M. Hillar, F. Prahl, eds., Vol. 6, pp. 44-78. American Humanist Association, Houston, 1998.

112 Immanuel Kant, Critique of Practical Reason, edited and translated with notes and introduction by Lewis White Beck, third edition, (New York: Macmillan Publishing Company, 1993), p. 90.

113 Cicero, On the Good Life, translated with an introduction by Michael Grant (Harmondsworth, UK: Penguin Books, 1986).

114 Charles Darwin, The Origin of Species and The Descent of Man and Selection in Relation to Sex (Toronto: Modern Library, reprint of the second edition of 1860, no date). p. 498.

115 Ibid. p. 499.

116 Ibid. p. 500.

117 Frans de Waal, with participation of Robert Wright, Christine M. Korsgaard, Philip Kitcher, Peter Singer, Primates and Philosophers. How Morality Evolved (Princeton and Oxford UK: Princeton University Press, 2006).

118 James H. Hunt, The Evolution of Social Wasps (Oxford: Oxford University Press, 2007). Bert Hölldobler and E. O. Wilson, The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies (NEW York: W. W. Norton & Company, 2008).

119 Martin A. Nowak, Evolutionary Dynamics: Exploring the Equations of Life (Cambridge, MA: Belknap Press of Harvard University Press, 2006).

120 Charles Darwin, The Descent of Man and Selection in Relation to Sex, op. cit. p. 471-472.

121 Elizabeth Pennisi, “On the Origin of Cooperation,” in Science, 4 September, 2009, Vol. 325, pp. 1196-1199.

122 Frans de Waal, Our Inner Ape. A Leading Primatologist Explains Why We Are Who We Are (New York: Riverhead Book, 2005). Frans de Waal, with participation of Robert Wright, Christine M. Korsgaard, Philip Kitcher, Peter Singer, Primates and Philosophers. How Morality Evolved (Princeton and Oxford UK: Princeton University Press, 2006).

123 Marc D. Hauser, Moral Minds. How Nature Designed Our Universal Sense of Right and Wrong, (New York: HarperCollins Publishers, 2006). Marc D. Hauser, “The Liver and the Moral Organ,” in Philosophy after Darwin, Michael Ruse, editor (Princeton, N.J., Oxford, UK : Princeton University Press, 2009), pp. 423-433.

124 Among modern philosophers, David Hume suggested that our notions of good and evil derive from very general principles expressed by our “sentiments.” David Hume, Enquiries Concerning Human Understanding and Concerning the Principles of Morals reprinted from the posthumous edition of 1777 and edited with introduction, comparative table of content, and analytical index by L.A. Selby-Bigge. Third edition with text revised and notes by P.H. Niddith (Oxford: Clarendon Press, 1992), pp 3-9.

125 John Rawls, A Theory of Justice, revised edition (Cambridge, Mass: The Belknap Press of Harvard University Press, 1971, 1999), pp. 40-46. Noam Chomsky, Aspects of the Theory of Syntax (Cambridge, Mass: The M.I.T. Press, 1965), pp. 3-9.

126Cicero’s view on human behavior coincides with that of Immanuel Kant who postulated categorical imperative as the maxim for human conduct. This maxim represents the highest level of understanding of morality and therefore he also postulated hypothetical imperative in which human behavior may be governed by other motifs. Immanuel Kant, Foundations of the Metaphysics of Morals and What is Enlightenment? Translated, with an Introduction by Lewis White Beck (New York, London: Macmillan Publishing Company, Collier Macmillan Publishers, 1988). Marian Hillar, “Is a Universal ethics Possible? A Humanist Proposition.” In The Philosophy of Humanism and the Issues of Today. American Humanist Association, Houston, 1995, pp. 127-148. In the final analysis reason is the basis for morality and philosophy produced very good intuitive theory how it works. Derek Parfit, Reason and Persons (Oxford: Clarendon Press, 1987). Jürgen Habermas, “A Conversation about God and the World,” in Time of Transitions, edited and translated by Ciaran Cronin and Max Pensky (Cambridge, UK: Polity Press, 2006), pp. 149-170. Modern science now grounds this philosophical intuition in evolutionary biological processes providing solid empirical foundations.

127 Summa Theologiae, op. cit., 1a 2ae, 71, a.2c.

128 E. O. Wilson, Sociobiology: The New Synthesis (Cambridge, MA: Harvard University Press, 1975). E. Westermarck, The Origin and Development of the Moral Ideas (London: Macmillan, 1908 (1912, 1917), Vol. 1-2. Frans de Waal, Our Inner Ape (New York: Riverhead Books, 2005). Frans de Waal, Primates and Philosophers. How Morality Evolved (Princeton and Oxford: Princeton University Press, 2006). Robert Wright, The Moral Animal. Evolutionary Psychology of Everyday Life (New York: Vintage Books, 1995). Robert Trivers, Natural Selection and Social Theory. Selected papers of Robert Trivers (Oxford: Oxford University Press, 2002).

129 Pascal Boyer, Religion Explained. The Evolutionary Origin of Religious Thought (New York: Basic Books, 2001). Marian Hillar, “What does Modern Science Say about the Origin of Religion” in Dialogue and Universalism, Vol. XXII, No. 4, 2012, pp. 111-120.

130 Friedrich Nietzsche, The Birth of Tragedy and The Genealogy of Morals, translated by Francis Golfing (New York: Anchor Books, 1990).