In denying the existence of God, atheism gets half the story right about the supernatural. The other half is about us, not God, and to complete the story is to adopt a consistent, thorough-going naturalism, a worldview based on a commitment to rational explanation and evidence. Naturalism says there’s a single natural world, the one science shows us, not a world divided up into the categorically natural vs. supernatural. Most atheists consider themselves naturalists in this sense, and indeed atheism is an expression or offshoot of naturalism.

In atheist circles it’s conventional wisdom to doubt God’s existence on empirical grounds: there’s no good evidence that such a being exists, so we don’t waste time believing in it. But there’s an equally suspect, supernatural entity that often lurks at the heart of commonsense ideas about human nature: the freely willing self.

We have, it is widely believed, the power to think, choose, and act in some crucial respect independently of those causal factors that create us as persons, and that surround us each moment of our lives. Unlike anything else in nature, human beings have a special contra-causal freedom to cause things to happen without themselves being fully caused in turn.

Sound familiar? It should, for such causally privileged freedom is a characteristic of God – the uncaused causer, the prime mover, who acts without himself being at the effect of anything. The assumption of free will, so widespread in our culture, in effect sets us up as supernatural little gods, and it’s this assumption that a thorough-going naturalism upsets. We should doubt the little god of free will on the very same grounds that atheists doubt the big god of traditional religions: there’s no evidence for it.

Just as science has radically altered our view of cosmic reality, replacing the static earth-centered heavens with the Big Bang, and supernatural human origins with Darwinian evolution, so too it replaces the soul with the fully physical person, shaped in its entirety by the complex interaction of genetics and environment. Rapidly accumulating evidence from biology, evolutionary psychology, and cognitive neuroscience suggests we are not causal exceptions to nature. There is no categorically mental agent or soul-essence floating above the brain which can exert a choice-making power that’s independent of neural processes. There’s nothing supernatural or causally privileged inside the head, just as there’s nothing supernatural outside it.

Of course denying our contra-causal freedom is psychologically fraught in very much the same way as denying God is for religionists. Most people, including some atheists, suppose that human dignity and efficacy depend on having contra-causal free will, and that without it the very basis for morality and law collapses. How can we take or assign credit and blame? How do we justify punishment or praise? Without free will aren’t we just puppets, mere mechanisms playing out our fates as determined by impersonal forces?

As pressing as such questions are, they have no bearing on the truth of the matter, which, if we are naturalists, we decide on the basis of evidence, not on what we suppose must be the case. And indeed, looking at the world and ourselves dispassionately and scientifically, there really are no evidential grounds for supposing we have supernatural souls, or any categorically mental, immaterial self that makes us freely willing little gods here on earth.

But this is OK. It turns out, on careful consideration, that any fears we might have about not having free will are groundless. Supernatural contra-causal freedom really isn’t necessary for anything we hold near and dear, whether it’s personhood, morality, dignity, creativity, individuality, or a robust sense of human agency. We may be fully caused in our choices and behavior, but that doesn’t render us ineffective in getting what we want, nor does it upset our moral compass: we can still tell right from wrong, and we’re still fully motivated to create a world in which we flourish, not perish. As Duke University philosopher Owen Flanagan argues in his ground-breaking book The Problem of the Soul, without free will we still have self-control, self-expression, individuality, rationality, moral accountability, and political freedom (see chapter 4, “Free Will”).

But further, and perhaps surprisingly, the realization that we are not little gods has considerable benefits, both personal and social. First, by accepting and illuminating our complete causal connection to the world, a consistent naturalism leads to a compassionate understanding of human faults and virtues. Seeing that we aren’t the ultimate originators of ourselves or our behavior, we can’t take ultimate credit or blame for what we do. This reduces unwarranted self-righteousness, pride, shame, and guilt. And since we see others as fully caused – for instance substance abusers, criminal offenders, the destitute and homeless – we become less blaming, less punitive and more empathetic and understanding.

Second, by seeing just how we are caused, by our genetic endowment, upbringing, and social environments, a naturalistic understanding of ourselves dramatically enhances our powers of prediction and control, both in our personal lives and in the larger social arena. In denying supernatural free will, naturalism focuses our attention on what actually determines human behavior. This increases our powers of self-control, and encourages science-based, effective and progressive policies in areas such as criminal justice, social inequality, behavioral health, and the environment.

Lastly, by showing we are fully included in nature, naturalism provides the basis for a satisfying approach to concerns about ultimate meaning and significance. Since we are not little gods, we find ourselves completely at home here on earth, part of an awe-inspiring universe, full-fledged participants in the unfolding natural order. As reported by Discover Magazine, Richard Dawkins has endorsed this sort of naturalistic spirituality, calling it “Einsteinian religion,” and arch-skeptic Michael Shermer conducted a seminar at Esalen on Science, Spirituality, and the Search for Meaning.

All this suggests that, if they haven’t already, atheists might expand their denial of the supernatural to include the little god of free will. In so doing they will become fully consistent in their naturalism, while accessing all its benefits. But from long experience in promoting naturalism, I know well the difficulties inherent in challenging free will. Even among the most hard-boiled atheists, some will balk at the idea that we don’t have contra-causal freedom. Nevertheless, this is the next step in freeing ourselves from supernaturalism.

Beyond denying the supernatural, naturalism holds great promise as an affirmative, comprehensive worldview that can compete with dualistic understandings of ourselves, whether these be traditional religions or new age philosophies. But it needs careful articulation in order to defuse fears and misunderstandings, and to show the full range of its psychological and practical advantages.

Tom Clark, January 6 2006