To speak truthfully is to accurately represent one’s beliefs. But candor offers no assurance that one’s beliefs about the world are true. - Sam Harris

Despite our attachment to the notion of free will, most of us know that disorders of the brain can trump the best intentions of the mind. This shift in understanding represents progress toward a deeper, more consistent, and more compassionate view of our common humanity — and we should note that this is progress away from religious metaphysics. Few concepts have offered greater scope for human cruelty than the idea of an immortal soul that stands independent of all material influences, ranging from genes to economic systems. Within a religious framework, a belief in free will supports the notion of sin — which seems to justify not only harsh punishment in this life but eternal punishment in the next. And yet, ironically, one of the fears attending our progress in science is that a more complete understanding of ourselves will dehumanize us.

Viewing human beings as natural phenomena need not damage our system of criminal justice. If we could incarcerate earthquakes and hurricanes for their crimes, we would build prisons for them as well. We fight emerging epidemics — and even the occasional wild animal — without attributing free will to them. Clearly, we can respond intelligently to the threat posed by dangerous people without lying to ourselves about the ultimate origins of human behavior. We will still need a criminal justice system that attempts to accurately assess guilt and innocence along with the future risks that the guilty pose to society. But the logic of punishing people will come undone — unless we find that punishment is an essential component of deterrence or rehabilitation.

Aesthetic experiences are still, more than likely, internal excitations of the brain, as we see from the fact that ingesting recreational drugs can bring on even more intense experiences of transcendence. And the particular triggers for natural aesthetic experiences are readily explicable from the evolutionary pressures that have shaped the perceptual systems of human beings

To say that something is “natural,” or that it has conferred an adaptive advantage upon our species, is not to say that it is “good” in the required sense of contributing to human happiness in the present.24 Admittedly, the problem of adjudicating what counts as happiness, and which forms of happiness should supersede others, is difficult — but so is every other problem worth thinking about.