The language of spirituality, so often entangled with supernaturalism, deserves to be liberated and reclaimed by those who seek truth without illusion. This leaves us the task of redefining it in ways that are compatible with a naturalistic worldview. If we wish to establish more unity among Spiritual Naturalists, it’s important that we rely on naturalistic definitions of spirituality that are inclusive of the diverse traditions and perspectives we find in SN. In this discussion, I will focus exclusively on naturalistic definitions of “spirit,” “spiritual,” and “spirituality.” Additionally, I will only mention authors who have written about naturalistic spirituality in a non-religious sense. Because this discussion is intended for naturalists, I will not make an attempt to define naturalism here.
Defining “Spirit”
Among Spiritual Naturalists, the term “spirit” evokes mixed reactions. Some strive to naturalize it, grounding the term in concepts that resonate with a scientific worldview. Others reject the term outright, but still accept “spiritual” and “spirituality.” Those who have attempted to naturalize it generally focus on either 1.) the etymological origins of “spirit,” 2.) common ways in which “spirit” is used naturalistically, or 3.) philosophical uses of the term. Each effort reflects a shared conviction—that “spirit,” properly understood, can illuminate what is essential in human existence without appealing to illusions or dogma.
The word “spirit” is often burdened with the weight of supernaturalism–a term hijacked to describe entities or forces for which we have no evidence. Yet, its origins are surprisingly grounded. “Spirit” comes from the Latin spiritus, a translation of the Greek pneuma. Both meant “breath” in their original usage, though they later took on deeper meanings. As the philosopher and former SNS Education Director Jay Forrest1 had noted, the breath was thought to be the vital principle in living things as the absence of breathing was the most obvious sign of death. Of course, today we know that when someone dies, the heart stops beating and the brain shuts down, causing consciousness to also shut down. Forrest noted that the ancient interpretation of spirit was not so much incorrect as incomplete; they did not fully understand death as the cessation of the heart and brain. Because we can now properly identify this vital principle as consciousness, Forrest argued that “spirit” is another word for “consciousness” or “awareness.” He doubled down on this approach by noting that one of the definitions of “spirit” in the Webster’s New World College Dictionary, is “life, will, consciousness, thought, etc., regarded as separate from matter.”
Professor of Philosophy Eric Steinhart once took a different approach to understanding the Greek “pneuma,” interpreting it through the lens of Stoic philosophy. For the Stoics, pneuma was the force driving the evolution of complexity in nature. Steinhart identified this as the extropic (complexity-driving) force that emerges from the Maximum Entropy Production Principle, or MEPP. According to this principle, ordered flows of energy produce entropy faster than disordered flows. Because the second law of thermodynamics states that processes in our universe tend or strive to maximize entropy, and because ordered flows of energy produce entropy faster, the MEPP entails that paths on which energy self-organizes are maximally attractive. Therefore, Steinhart saw spirit as the extropic force that emerges from the MEPP2.
However, Steinhart was careful to distinguish this naturalistic “spirit” from any supernatural notion. As a thermodynamic force, Steinhart noted that spirit has no mentality, intentionality or volition, describing its directionality as “mindless.” It is a force of nature, indifferent to the human condition, and, as with all thermodynamic principles, it operates statistically—its outcomes are not guaranteed, and its trajectories can fail. This view invites us to reimagine spirit as an emergent, directionless force intrinsic to the universe—a force that, while devoid of consciousness, can play a vital role in the unfolding complexity of existence.
In his book, Your Digital Afterlives, Steinhart observed that many thinkers have argued complexity itself is equivalent to intrinsic value. Consequently, in his paper Spirit, he argued, “spirit strives to increase those intrinsic values” and that spirit “is a value-increasing power.” In a later presentation, he argued that spirit increases values through humans, describing it as the striving of the goods of the body by striving for health, virtue, justice in society, and ecological harmony.
Interestingly, there is some overlap between Forrest’s and Steinhart’s former definitions, as the force that Steinhart described is what generates consciousness in nature. Without the MEPP (or at least something like it), complex phenomena such as consciousness could not exist. Therefore, we could say that “spirit” as Steinhart defined it drives the existence of “spirit” as Forrest defined it. The difference is Forrest’s former definition of spirit is confined to the individual and ceases to exist after death, while Steinhart’s former definition of spirit is a universal force that continues to exist after one dies. “Spirit,” as Forrest defined it, additionally doesn’t strive through human bodies as it does in the way Steinhart defined it. At the very most, it is merely the localized experience of this striving—a fragment of the larger processes at work in the cosmos.
Despite Steinhart’s compelling argument for spirit, he ultimately abandoned the term in his later work, Believing in Dawkins, adding that the word is “too corrupted to reclaim.” He now advocates the term “axiotropy” to refer to the extropic force that emerges from the MEPP. Yet, there are contemporaneous uses of “spirit” that trace back to its origins. Daniel Strain, founder of the Spiritual Naturalist Society, reminds us that “spiritus” also meant “the essence of something,” and that this meaning persists in expressions like “the spirit of the law” or “school spirit.” Strain’s interpretation is also more inclusive of Forrest’s and Steinhart’s prior definitions as consciousness is essential to the human experience and axiotropy is essential for the existence of complexity. So according to Strain’s framework, “spirit” is “essence,” “spiritual” is “essential,” and “spirituality” is the “state or quality of being essential.”
What about other naturalistic uses of the word? For SNS Editing Director Thomas Schenk, “spirit” pertains to the part of our inner being “that is verbal and capable of setting and pursuing goals, of being intentional.” He considers it identical to what the ancient Greeks, and particularly the Stoics called the rational mind. This part of our being can provide structure to the random elements of the mind. Schenk additionally contrasts “spirit” with “soul” which he considers to be the nonverbal part of his being such as imagination, dreams, emotions, impulses, intuitions, etc. Yet to Schenk, spirit and soul are not opposites; they are complementary, inseparable, and mutually dependent. In his view, spirit is tethered more closely to the mind, while soul more closely relates to the biological concerns of the body. He uses the metaphor of pottery to describe this relationship: the soul provides the raw material—the clay—while the spirit shapes it. This perspective positions “spirit” as an essential dimension of the human experience, grounded in our cognitive and biological nature.
The philosopher and professor Robert C Solomon gave many meanings to “spirit.” He used it to refer to states of mind, such as “being in good spirits,” or “needing one’s spirits raised.” He also defined it as a “nonmystical shared passion,” such as in “team spirit,” or “spirit of the times.” Interestingly, he also argued that nature, too, can have a spirit, “insofar as the beholder of nature has one.” These uses of the term resonate deeply with Strain’s notion of spirit as “essence,” as Solomon treats good states of mind and shared passion as essential matters of life.
Naturally, some thinkers have sought to articulate more philosophical definitions for their spiritual framework. Forrest‘s and Solomon’s definitions of “spirit” are partially inspired from Georg Wilhem Friedrich Hegel’s use of the term in The Phenomenology of Spirit (though they differ in their interpretations). The French philosopher André Comte-Sponville by contrast, adopts and extends René Descartes’ definition of spirit as “a thing that thinks,” encompassing its various faculties: doubting, affirming, denying, desiring, imagining, and perceiving. Comte-Sponville elaborates on this, describing spirit as “a thing that loves, that does not love, that contemplates, that remembers, that mocks or jokes.” Put succinctly, Comte-Sponville considers spirit to be “the power to think, insofar as it gives us access to truth, universality or laughter.” He considers spirit in this way to not be a substance, but rather an immanent function, capacity, and act. However, Comte-Sponville insists that spirit is not identical to the self, but exists as a grand “openness” that sets us free from the contemptible self. Comte-Sponville further asks “What could be better, loftier or more fascinating than the spirit? Not believing in God is no reason to amputate a part of our humanity, especially not that part!” In this way, he frames spirit as essential, not as a metaphysical relic, but as a profound dimension of human experience that transcends mere belief.
Here, we see that half of the issue with defining “spirit” naturalistically (with the other half being the supernatural hijacking of “spirit”3) is that there is no singular “essence” that can encapsulate the richness of life. Rather, there are many essential aspects to existence that are emphasized differently among different people. To see if defining “spirit” in this way holds up, let’s now turn to naturalistic definitions of “spiritual” and “spirituality,” alongside the concept of “spiritual naturalism.”
Defining “Spiritual”
Despite his rejection of “spirit,” Steinhart fully embraces the use of terms like “spiritual” and “spirituality.” He considers more highly self-organized things to be more spiritual, and therefore sees the extropic force that emerges from the MEPP as striving to become more spiritual. Within Steinhart’s framework, to be more self-organized is to be more valuable, and thus his concept of “spiritual” is not merely descriptive—it is essential to the very existence of value itself. This perspective resonates with and complements Strain’s expansion of “spirit” into “spiritual,”
Like Steinhart, psychologist and lecturer Susan Blackmore rejects “spirit,” considering the word “spiritual” to be “a terrible word” due to its association with supernatural spirits. Yet, she welcomes calling herself a Spiritual Naturalist, as she can’t think of a better word for what she thinks of as her ‘spiritual practice.’ She adds that when naturalists refuse to throw out what could be called a ‘spiritual life,’ ‘spiritual practice’ or spiritual path,’ many great questions arise. Among these questions she includes: 1.) “How does compassion arise in a natural world?” 2.) “What does wisdom mean?” 3.) “How can we share and respect spirituality without falling into dogma and religion?” 4.) “How can we understand the transformations that take place in those who practice meditation and mindfulness?” 5.) “Where does human happiness fit in?” 6.) “And gratitude, and death, and love?” In light of Blackmore’s perspective, it becomes clear that these are not peripheral musings—they are essential questions.
Philosopher and neuroscientist Sam Harris echoes Blackmore’s sentiment on the need for the word “spiritual” in a naturalistic context. He adds:
“there is no other term—apart from the even more problematic mystical or the more restrictive contemplative—with which to discuss the efforts people make, through meditation, psychedelics, or other means, to fully bring their minds into the present or to induce nonordinary states of consciousness. And no other word links this spectrum of experience to our ethical lives.”
To Harris, a spiritual life within this framework is essential to a good life, once again holding up to Strain’s definition.
What of those who have embraced the term “spirit?” Does their expanded definition, encompassing “spiritual,” hold up under scrutiny? Forrest, who defined “spirit,” as “consciousness,” expanded this definition to “the expansion or deepening of consciousness.” More precisely, he defined it as “the expansion or deepening of awareness of union and communion with reality.” He provided examples of how this definition can apply to various spiritual traditions: for Christians, this reality is God; for Hindus, it’s Brahman; and for Naturalists, it’s nature. This is a generous and inclusive definition, seeking to unite diverse traditions under the shared experience of communion with something greater than the self. It respects the particularities of belief while pointing to a common ground. Yet, one might wonder if defining “spiritual” in terms of what is “essential” could offer a deeper universality. While Forrest’s former definition anchors spirituality in a profound sense of connectedness, the broader notion of “essential” may better capture the diversity and depth of human spiritual experience.
Defining “Spirituality
It should be noted that Strain offers a slightly expanded definition of “spirituality,” framing it as concern with “the larger, deeper, and essential matters of life,” and applying ourselves toward them “in a committed practice or ‘walk’.” Here, we see that he is providing a practical definition that applies spirituality to human lives. As we proceed through this section, it will become clear that none of the definitions that follow stand in opposition to Strain’s view, even in its expanded form. Instead, they complement and reinforce the idea that spirituality, at its core, is about engaging with the essential dimensions of life in a deliberate way.
Like Steinhart, Blackmore, and Harris, Gregory Gronbacher, scholar and former SNS Executive Director, rejects the term “spirit.” Though I’m not aware of him providing a specific definition for “spiritual,” he writes that “Many of us have retained the word and use it to describe various emotions, reactions, and attitudes, such as wonder, gratitude, joy, love, and awe.” More broadly, he describes spirituality as concerning “the arena of human meaning and core issues of purpose and being alive.” These emotions, reactions, and attitudes are deeper, essential qualities to our lives, further confirming Strain’s definition.
Expanding on the need for the word “spiritual,” Harris elaborates that by “spirituality” he means the deepening of a clearer understanding of the way things are, and “repeatedly cutting through the illusion of the self.” He considers spirituality “not just important for living a good life,” but also “essential for understanding the human mind.” Here, the alignment with Strain is unmistakable.
On defining “spirituality,” Forrest agreed with Strain’s definition, but observed that Strain doesn’t say what the “essential matters of life” are. He therefore expanded upon his definition of spirituality to denote the “purposeful development of the quality or state of an expanded or deepened awareness of our union and interconnect with nature.” Forrest was correct that Strain’s definition doesn’t specify “the essential matters of life,” but I think this is for the better. A strict definition of “spirituality might come across as dogmatic or authoritative. Given that naturalism is inherently provisional, it follows that a naturalistic approach to spirituality should remain equally open-ended. A broad and flexible definition invites dialogue, keeping the exploration of essential matters alive and evolving.
In The Philosophy of Spirituality, Eric Steinhart offers a strikingly precise definition of spirituality, describing it as ”the degree of self-organization” in a thing. He critiques definitions that emphasize psychological qualities like meaning and purpose, arguing that such terms are often vague and imprecise. For Steinhart, any definition of spirituality should rest on mathematical precision and empirical measurability. Within this framework, Steinhart notes that self-organization in humans is self-regulation and self-control, and that organisms with higher self-control have greater spirituality. Because self-control can be measured through behavioral tests, fMRI scans, and EEGs, Steinhart argues that spirituality in humans is quantifiable. In Ritual Kindles Vision however, Steinhart defines “spirituality” slightly differently: as “the craft of ethical self-surpassing.” At first glance, this may seem distinct from his earlier formulation, but Steinhart links ethical self-surpassing in humans to higher levels of self-control. One definition provides a measurable, scientific account of what spirituality is, while the other addresses its purpose and function. Both relate to essential matters.
Building on his definition of “spirit,” Thomas Schenk notes that it would follow that “spirituality is primarily about living intentionally and rationally,” though he believes this definition is too narrow. In Schenk’s view, spirituality “is active, creative, and transformative,” and centers around “the transformation of the formless and random into the structured and organized.” This includes the integration of the spirit and the soul as he defined it, which he likens to the interplay of yang and yin in Taoism. Ultimately, Schenk considers spirituality to be “about bringing form to the formless and light to the darkness,” and taking it in a different direction. Though he is quick to clarify that spirituality in this way, is more about experience than beliefs. More succinctly, Schenk distills his understanding of spirituality into the concept of mindfulness, which he considers to be “the jewel of spirituality” and “the alpha and omega” of his spiritual practice. He also considers communion to be central to spirituality as the “experience of communion merges the inner experience of mindfulness with the outer experience and knowledge of the cosmos.” This synthesis underscores his view of spirituality as a “quest for communion,” emphasizing connection as both the journey and the destination of a spiritual life. Here, we again see a Spiritual Naturalist discussing states and qualities that are essential to the human experience.
Similarly, Solomon also expanded on his definition of “spirit,” defining “spirituality” as “the thoughtful love of life.” Similar to Steinhart and Schenk’s definitions, he added that spirituality in this form, is the organization of life, and ultimately the same thing as wisdom. He compared it to music, suggesting that it is a celebration of life that we feel “in our bones.” Within this larger sense of life, Solomon meant that we see beyond ourselves and then to nature. Though he initially dismissed the term earlier in his career, he later came to recognize it as “an essential dimension of life.”
Lastly, Comte-Sponville expands on his definition of “spirit,” considering spirituality to be “the life of the spirit.” For him, it is the function, capacity, and act of opening ourselves from “the contemptible self” to “truth, universality, or laughter.” In his vision, spirituality becomes a way of seeing and being, a quiet but transformative alignment with the essential realities of life.
Defining “Spiritual Naturalism”
So “spirituality” is the quality of being concerned with the “deeper, more essential matters of life.” It should be noted however, that “spirituality” defined naturalistically, and “Spiritual Naturalism,” imply slightly different things. The suffix “-ity” in “spirituality” implies a state or quality. On the other hand, “-ism” in this sense, implies a category of some sort. This is likely why Forrest considered “Spiritual Naturalism” as “the big umbrella under which a number of branches belong.” He included Buddhist Naturalism as a branch on this tree, though he also mentioned Secular Buddhism4, Naturalistic Paganism, Stoicism, Humanism, and Pantheism.
Similarly, Steinhart considers SN to be an umbrella group, but instead of using Forrest’s metaphor of branches, Steinhart describes SN as including different departments. He adds that one of the primary purposes of SN is to get these departments to talk to each other and see how they relate. This, in essence, is the role of Spiritual Naturalism: to unify diverse approaches to life’s essential questions and promote human flourishing on a global scale through shared understanding and cooperation.
Yet, SN need not be confined to the boundaries of tradition. While traditions provide valuable frameworks, they are not prerequisites for engaging with the principles that underlie a spiritual life. For instance, Schenk’s view of Spiritual Naturalism can be summarized around several core themes, including mindfulness, the Big Story of the universe, mystery, and communion. Here, we see that Schenk is listing elements belonging to the category of “deeper, more essential matters of life” from a lens that transcends the limits of tradition. SNS writer and Council Member James Jarrett additionally shares a tradition-free approach to SN, describing Spiritual Naturalism as “an evidence-based approach to spirituality that finds the sacred within the natural order of the Universe and invites human participation in the sacred through awareness, meaningful ritual, and practice.” This framing, much like Schenk’s, focuses on the essential core elements that he considers as belonging to SN—elements that transcend any particular tradition and instead ground spirituality in experience, reason, and our inherent connection to the natural world.
Lastly, Gronbacher describes Spiritual Naturalism as:
“a worldview that combines a naturalistic understanding of the universe with an appreciation for spirituality and the sacred. It is a way of looking at the world that acknowledges the beauty and wonder of nature and the universe while rejecting supernatural beliefs. It relies on reason, science, and evidence-based thinking to understand the world and our place in it.”
Gronbacher’s approach to SN does not pertain to a particular tradition, but involves a framework of several core ideas including: 1.) An emphasis on the natural world, 2.) The rejection of supernaturalism, 3.) An existential understanding of spirituality, 4.) Interconnectedness, 5.) Ethics and morality, 6.) A diversity of practices, and 7.) Connection to science. Here, Spiritual Naturalism emerges as an inclusive umbrella concept, uniting not only traditions but anything that addresses “the deeper, more essential matters of life.” In other words, “Spiritual Naturalism” is about what’s profoundly important. It refers to relevance—what matters most, what is worth our attention and care. Therefore anything in the natural world that pertains to ultimate concern can be said to be a droplet in the vast ocean that we call “Spiritual Naturalism.”
__________
Learn about Membership in the Spiritual Naturalist Society
The Spiritual Naturalist Society works to spread awareness of spiritual naturalism as a way of life, develop its thought and practice, and help bring together like-minded practitioners in fellowship.
SNS strives to include diverse voices within the spectrum of naturalistic spirituality. Authors will vary in their opinions, terms, and outlook. The views of no single author therefore necessarily reflect those of all Spiritual Naturalists or of SNS.
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Notes:
1. Forrest is no longer a naturalist and has since criticized naturalism. Because this article is for naturalists, I will not discuss his refutation of naturalism here. I will refer to his prior works on Spiritual Naturalism however, as they have had an influence within the Spiritual Naturalist community.
2. Steinhart notes in Believing in Dawkins that although a great deal of evidence in physics, chemistry, biology, ecology, and economics supports the MEPP, it’s still not fully confirmed as a physical fact. He adds that the MEPP may be modified, and that it’s likely that something like the MEPP will turn out to be a law of physics.
3. See my article, Spirituality for Skeptics: Why Rationality Needs the Sacred for more on the supernatural hijacking of spirituality.
4. Forrest made a distinction between Secular Buddhism and Naturalistic Buddhism in his book, Spiritual Naturalism. He described Secular Buddhism as starting with Buddhism and then attempting to secularize it, while Naturalistic Buddhism starts with naturalism, and then builds on in with Buddhist teachings
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