I first read C.S. Lewis’s Miracles about 25 years ago, and it was pretty important in what eventually turned out to be my return to Christian faith, over a decade after I had abandoned belief in God when I was a teenager. It helped me see that Christianity–and not just a watered-down, “modernist” version–might actually be true.
Re-reading it recently I was struck once again by Lewis’s insistence that “reason,” by which he means our faculty for logical argument, as well as for apprehending moral truth, must be “supernatural,” at least relatively speaking. That is, if our reasoning is determined by natural laws of cause and effect (the great, interlocking system of nature, as he puts it), then what justification do we have for thinking that it provides a path to truth? Only if our thinking can, at least sometimes, operate according to the laws of logic rather than the laws of cause and effect can we trust our ability to apprehend truth. Human minds–or at least this part of them–must originate outside the natural world. This is the key argument Lewis makes to show that naturalism is untenable (and a pivotal part of his argument that miracles are at least possible).
However, Lewis’s rather stark version of dualism won’t sit well with everyone. On his view, human spirits (i.e., the part of us capable of abstract thought and moral reasoning) are “inserted” as it were at various points in the natural wold, rather than being fully integrated parts of that world. That’s his point after all–if they were fully part of the natural world we would have no grounds for trust in our reasoning capabilities. But this seems a bit inelegant and ad hoc. Wouldn’t it be better to have an account that showed human minds were fully a part of nature but didn’t undermine the trustworthiness of reason? Even from a theistic perspective, wouldn’t it be more fitting and elegant to say that God created a universe that was capable of producing reasoning creatures from within?
These considerations are at least part of the motivation for various forms of “non-reductive” materialism or “emergentism” that have become popular among some Christian theologians and philosophers. On this kind of view, mind and consciousness develop from material organisms once they attain a certain level of complexity, but once they do, these emergent minds achieve a degree of independence.* For example, non-reductive materialists and “emergentists” maintain that causality between the mental and the physical goes both ways: our thoughts and decisions really affect the way things go, and this is not reducible to or fully explicable in terms of their physical substratum. If I get up from my desk and walk across the street to the local coffee shop, this action has to be explained (at least in part) by the contents of my thoughts. The mental has a genuine (if partial) causal independence and operates according to its own laws and principles. Another way of making the point is to say that purposive actions–doing things for a reason–are an inelminable feature of reality.
This type of view is attractive because it allows us to see human beings as part of the natural world without sacrificing the reality and efficacy of consciousness (as so-called “reductive” or “eliminative” forms of materialism do). From a Christian point of view, it seems to offer a more holistic account of the human person which is (so it is claimed) more consistent with the way human beings are portrayed in the Bible. This contrasts with forms of dualism that characterize the soul as wholly distinct from, or even trapped in, the body–a position sometimes associated (not entirely fairly) with Plato and Descartes. It also can seem more consonant with the resurrection of the body as the main focus of our hope for life after death.
This account isn’t without its own problems though. One is that it’s not obvious that the notion of an “emergent mind” is any clearer than full-blown dualism. It’s very hard to show how mind and consciousness could “emerge” from a particular arrangement of matter since the properties of matter and mind seem so different. This is, after all, one of the main motivations for both dualism and non-reductive materialism: thoughts have properties–they’re non-spatial, essentially private, are about something–that matter doesn’t, so they can’t be the same thing.
It’s true that there are examples of new properties that seem to “emerge” from a particular organization of matter (e.g., the liquidity of water is not a property of hydrogen or oxygen molecules, but rather comes into existence when they are brought into a particular relation); but there aren’t other obvious examples of a non-physical property or capability emerging from the physical. This raises the question of whether “emergence” is a solution to the problem or just another way of stating it.
There are many varieties of dualism and materialism, as well as other views like “dual-aspect monism,” and I haven’t kept up with recent philosophy of mind (not to mention other relevant fields like neuroscience!) enough to have a strong view about which one’s right (if any). I do think there are good arguments that mind and consciousness can’t be reduced to or simply identified with physical events, even though there’s obviously a strong correlation between them. What I’m less certain of is whether this means we have “souls” that are somehow independently created substances or whether our minds are functions or products of our brains and bodies that nevertheless posses a certain degree of independence.
I still think Lewis’s argument is convincing against a strict, reductive form of naturalism. If our minds really are nothing but brain events operating according to the inexorable laws of cause and effect, then it is hard to see how we could trust them as tools for acquiring true beliefs or maintain that we (sometimes) act for reasons rather than because of blind causality. But it may be that this insight can be accommodated by a more generous form of physicalism or non-dualism.
This might seem to undermine Lewis’s argument for theism and miracles, but a modified version of the case is possible. The fact that our universe is of the sort that can give rise to rational beings capable of moral choice could be taken to indicate that our cosmos is the result of a purposive mind. Because they are irreducible features of the world, mind, purpose and values, it could be argued, are clues to the character of the universe as a whole. They needn’t be seen as interruptions into the normal course of nature to be suggestive of nature’s origin–and of its potential openness to divine action.
*Lewis focused the parts of the human mind responsible for abstract reasoning (e.g., logical inference) and the apprehension of moral truth. He allowed that the “lower” parts of our minds (sensations, emotions, etc.) were fully natural. Other philosophers and theologians focus more on the problem of consciousness itself and its irreducibility to the physical. However, one thing all parties would agree to I think is that our minds have a certain causal independence: i.e., what we think or decide can make a difference to the course of events in a way that isn’t entirely determined by or a by-product of physical causes.