From Faith to Naturalism: a personal journey

By Ron March

Ron is a retired religious education teacher and a member of West Dorset Humanists. In this augmented version of a short talk he gave at Dorset Humanists, he shares his personal journey from Christianity to Naturalism, tracing a thoughtful path through radical theology, the Sea of Faith movement, and into a worldview grounded in reason, evidence and the scientific method. Drawing on the insights of physicist Sean Carroll, Ron explores why he no longer believes in a supernatural dimension to existence—and why Naturalism, as both a philosophical stance and a way of life, deserves greater understanding and emphasis within the humanist movement.

I want to begin by sharing a little about myself, to give some context for where I find myself now. In my youth, I was drawn to Christianity as a framework for making sense of life’s big questions. That path led me to become a Religious Education teacher, a role that challenged me in unexpected ways. The questions my students asked—sometimes searching, sometimes sceptical—forced me to think more deeply than ever before.

As my understanding of the universe and of what it means to be human expanded, my ideas began to shift. I started to describe myself as a radical Christian, someone still rooted in the tradition but open to reimagining its meaning in the light of reason and experience. In the 1980s, I encountered the Sea of Faith Network, which explored religion as a human creation rather than a revelation of divine truth. That discovery was a turning point. Gradually, I found I could no longer believe in a supernatural dimension to existence.

About 14 years ago, through Sea of Faith, I became aware of Naturalism, and it has since shaped the way I think about life, the universe, and human purpose. I now see myself as aligned with both Naturalism and Humanism—two perspectives that value human understanding, ethical living, and our shared responsibility for the future.

Presuppositions and the courage to change

In the weeks leading up to writing this, I found myself reflecting on how much our thinking is shaped by the presuppositions we carry—often without realising it. These underlying assumptions can powerfully influence the way we interpret the world, understand ourselves, and engage with others. It’s also worth remembering that words, concepts, and ideas are products of human minds, shaped by culture, language, and experience. Without human beings, none of these things would exist. They are tools we use to make sense of reality—but like all tools, they are limited and provisional.

As our knowledge grows, we have a responsibility to revisit and revise our beliefs. That takes courage. It means being open to changing long-held views in light of new understanding. And the more we discover—about the universe, about life, about ourselves—the more we realise how much we still don’t know. Each of us must live in the light of what we currently understand, while remaining open to further exploration. In that spirit, I’ve come to embrace a more naturalistic view of the world—not as a final answer, but as a framework that makes better sense of what we know so far.

Seven questions about Naturalism

These reflections led me to explore Naturalism through a series of questions—questions that helped clarify my own thinking and may be helpful for others on a similar journey.

1. What is Naturalism?

Naturalism is the view that the natural world is all that exists. It holds that there is no need to appeal to supernatural or transcendental entities to explain the universe or our place within it. Naturalism denies the existence of gods, spirits, or other supernatural forces. It asserts that natural laws govern everything—from the behaviour of galaxies to the workings of the human brain. To understand the world, Naturalism promotes the use of reason, evidence, and the scientific method.

2. What is the scientific method?

The scientific method is a systematic way of acquiring knowledge. It involves careful observation, forming hypotheses, designing experiments, analysing data, and drawing conclusions. Science uses this method not only to explain specific phenomena, but also to refine or revise our understanding over time. It is, in essence, a self-correcting process—open to new evidence and always subject to improvement.

3. What does Naturalism say about the scientific method?

Naturalism maintains that the scientific method is the most reliable way we have to investigate and understand reality—including human consciousness, values, and meaning. Because Naturalism holds that nature is the only reality, it affirms that all phenomena, including those related to human experience, can be understood through natural processes and laws. While not denying the richness of human life, it insists that even our deepest experiences arise from within the natural world.

4. What does Naturalism say about the Cosmological Argument for the existence of God?

The Cosmological Argument claims that everything that begins to exist must have a cause—and therefore the universe must have a cause, typically understood to be God. Naturalism challenges this reasoning by asserting that all phenomena arise from natural processes, and that there is no need to posit a supernatural cause for the universe. Some naturalists argue that the universe exists necessarily, while others see it as a brute fact that requires no further explanation. There are also naturalistic models in which the universe is eternal, or originates from an eternal set of conditions. For a more detailed exploration of this topic, see the discussion of Sean Carroll’s perspective later in the article.

5. What does Naturalism say about the Fine-Tuning Argument?

The Fine-Tuning Argument suggests that the physical constants of the universe appear so precisely calibrated for life that a designer must be responsible. Naturalism offers several alternative explanations. These include the multiverse hypothesis, the possibility that fine-tuning is a necessary outcome of fundamental laws, or that it reflects an observational bias—we can only observe a universe that permits life because we are here to observe it. Physicist Sean Carroll has written and spoken extensively on this topic, offering a naturalistic critique of fine-tuning arguments and proposing alternative ways to understand the appearance of design. His perspective is discussed later in this article.

6. What does Naturalism say about Deism?

Deism posits a distant, non-interventionist creator God who set the universe in motion and then left it to run according to natural laws. Naturalism rejects even this minimal supernatural claim, arguing that there is no need to posit a creator at all. Everything in the universe, it maintains, can be explained by natural causes and processes without invoking any divine intelligence—active or passive.

7. What does Naturalism say about the origin of the universe?

Naturalism proposes that the universe originated through natural means, not by the will of a supernatural creator. The most widely supported scientific model suggests the universe evolved from a singularity—an extremely hot and dense point from which space and time themselves expanded.

While we may not yet fully understand the origin of everything, Naturalism holds that the answer, when found, will be within nature, not beyond it.

Sean Carroll: a scientific voice for Naturalism

Several years ago, I encountered the work of Sean Carroll, an American physicist known for his expertise in quantum mechanics, cosmology, and the philosophy of science. Carroll is also a prominent public intellectual, widely recognised for his atheism, his critique of theistic arguments, and his robust defence of Naturalism. His reflections in three major areas—the Cosmological Argument, Fine-Tuning, and the scientific method—have been especially influential in shaping my own understanding.

1. The Cosmological Argument and Causation

The Cosmological Argument asserts that everything that begins to exist must have a cause. Since the universe began to exist, the argument goes, it too must have a cause—identified as God. Carroll challenges this line of reasoning on several fronts. First, he questions whether the universe necessarily began to exist in the way the argument assumes. At the level of cosmology, the beginning of the universe is not as clear-cut as everyday experience might suggest. In fact, the very concept of time may not apply at the Big Bang in the way we’re used to. He also questions whether our ordinary understanding of causation—which comes from within the universe—can meaningfully be applied to the universe as a whole. Causation, he suggests, might not be a fundamental feature of reality, but a derived concept that doesn’t apply at the deepest levels of physics.

2. The Fine-Tuning Argument and the Multiverse

The Fine-Tuning Argument holds that the physical constants of the universe appear to be precisely calibrated for life. For many, this suggests the presence of an intelligent designer. Carroll responds by pointing out that we don’t actually know the range of conditions under which life could exist, nor do we fully understand whether these constants are fixed or necessary. He offers the multiverse as a compelling naturalistic alternative: if countless universes exist, each with different properties, it’s not surprising that at least one would support life—and that we happen to find ourselves in that one. Moreover, he notes that if a God had designed the universe with life in mind, we might expect it to look very different—perhaps more hospitable, less violent, and less indifferent to suffering. The universe we observe does not obviously reflect intentional fine-tuning for human wellbeing.

3. Naturalism and the Scientific Approach

Carroll stresses that science is not in the business of proving or disproving God’s existence. Instead, it seeks to develop and test explanations that are coherent, evidence-based, and elegant. He argues that theistic explanations often fall short of this standard. They tend to introduce unnecessary complexity, rely on ad hoc reasoning, and offer little in the way of testable predictions. By contrast, naturalistic explanations—even if incomplete—are more intellectually disciplined and grounded in empirical observation. Carroll’s work has helped me see that naturalism doesn’t close down wonder or inquiry—it deepens it. His approach encourages us to embrace mystery, not with supernatural assumptions, but with intellectual humility and a commitment to discovering how things really are.

Why I no longer believe in a supernatural dimension

Having explored these ideas over many years—through science, philosophy, and personal reflection—I have reached a point where I can no longer accept that there is a supernatural dimension to existence. The reasons are not emotional, but intellectual and experiential. They are grounded in a view of the world that feels more coherent, more honest, and more open to growth.

Here are some of the key reasons why I now see the universe through a naturalistic lens:

1. There are natural explanations—backed by evidence and ongoing research—for the origin of the universe and of human life. These explanations are incomplete, but they continue to grow more compelling.

2. Gods, spirits, and other supernatural entities can be understood as human creations—psychological, cultural, and historical expressions of our attempt to make sense of the unknown.

3. So-called miraculous phenomena often have natural explanations, or at least can be approached with curiosity rather than supernatural assumptions.

4. The problem of pain and suffering remains, for me, one of the strongest arguments against a benevolent, omnipotent deity. Suffering is not a moral puzzle when seen through a naturalistic lens—it is a reality of biological life, shaped by evolution and circumstance.

5. Sacred texts, including the Bible, no longer strike me as the literal word of a divine being. They are profound and sometimes beautiful documents—but created by human beings, for human purposes.

In sum, Naturalism makes more sense to me. It does not claim to have all the answers, but it invites us to seek them through evidence, dialogue, and honest inquiry. It acknowledges mystery without inventing answers. And it encourages us to take responsibility—for our beliefs, our ethics, and our shared future.

Related viewing and listening

• Sean Carroll, God & Cosmology debate with William Lane Craig, available on YouTube (2 hrs 16 mins)

• BBC Radio 4, Writing the Universe: In the Beginning, featuring Robin Ince, Brian Cox, and Sean Carroll (April 2024)