This is the argument that had received the least amount of attention up until the modern era. This will be much more than simply posing the challenge: Can matter think? Could reason have evolved from non-reason? Those are great questions, of course, but they remain questions and not demonstrations. Indeed they are not even arguments if left to themselves. 

Lewis’ “Cardinal Difficulty with Naturalism”

In C. S. Lewis book on Miracles, he began with a description of the fundamental question as one between the Naturalist and the Supernaturalist. Naturalists are those who believe that Nature is all there is. The word nature, from the Latin natura, has the connotation of that which goes on of its own accord. Applied to the whole cosmos “nature” is really a synonym for “the whole show.” Hence nothing can claim independence from the system of “all there is.” Everything belongs to what he would call an interlocking series of cause and effect. Now such a view more obviously excludes the possibility of free will and moral ought-ness. But what Lewis begins to show is that it actually does the same to reason.

In a chapter entitled “The Cardinal Difficulty with Naturalism,” Lewis began to unpack this argument, first with a conditional proposition: If Naturalism is true, then absolutely everything must be “explicable in terms of the Total System” [1]. Recall that by this “System” is meant an infinite series of interlocking cause and effect.

What follows is that absolutely all events (or effects) are bound to have taken place in exactly the way that they have. Interlocking cause and effect implies inevitable cause and effect: in short, full, natural determinism. But if this is true of all events, and if mental events are events, then by resistless logic, it is also true of all mental events.

Let us say that Mind A (possessing Mental Event 1) and Mind B (possessing Mental Event 2) disagree about some fact or figure. Now ordinarily we would appeal to some idea as a standard by which to judge the truth or falsity of the two opposing propositions. This idea may be a matter of deductive logic, or quantity, or physical measurement, or an authority from history.

Even such things as a ruler or calculator or scientific consensus ultimately reduce to ideas, as each of these signals the very normative meaning that it does precisely as an object of thought, ideas that other minds are expected to understand as more than a mere slice of plastic (the ruler), or slightly fancier scrap of plastic with bytes (the calculator), or the group of special people with still slightly fancier scraps of plastic hanging on their walls with the letters “P-h-D” (the scientific consensus).

But whatever it is, that standard will have been formed (and continues to operate) as an idea that is itself apprehended by minds. Both its origin and its destination are minds. In other words, an objective standard for truth verification is really a third idea, a third mental event, alongside of the original two ideas which are in opposition. But an insurmountable difficulty arises within the Naturalist’s model. Each of those mental events (Now “Mental Events 1, 2, and 3”) must be subject to the same fate, at least in that they are an inevitable consequence of the interlocking causal chain. Not one of them could have been anything other than what they are.

Thus there can be no privileged standard to judge between the beliefs held by one mind, as opposed to another, for that “standard” is itself a belief—no more and no less than the claim to insight as the two other propositions it is supposedly judging between—and is as equally caused by the bounded System as any other. Supposing someone wants to object: “No—objective standards are more than mere ideas.” Whatever their defense of this, their defense will amount to a fourth idea. How shall we judge between the claims of Idea 3 (the proposed standard), together with Idea 4 (defense of that standard) and the claims of Idea 5 (any objection to the proposed standard and said defense)? Answer: a sixth idea. Quite obviously an infinite regress has commenced. But it may be asked whether Lewis has made a straw man either of the Naturalist’s position or what it entails. 

We need to take a step back and ask what are the prerequisites to valid and sound reasoning, on any view (for any true theory). In perhaps the most important paragraph, Lewis says this,

All possible knowledge, then, depends on the validity of reasoning … Unless human reasoning is valid no science can be true. It follows that no account of the universe can be true unless that account leaves it possible for our thinking to be a real insight. A theory which explained everything else in the whole universe but which made it impossible to believe our thinking was valid, would be utterly out of court. For that theory would itself have been reached by thinking, and if thinking is not valid that theory would, of course, be itself demolished. It would have destroyed its own credentials. It would be an argument which proved that no argument was sound—a proof that there are no such things as proofs—which is nonsense [2]. 

Naturalism is thus self-contradictory. The position as a whole can be reduced to the logically equivalent: No mental event is an objective insight into the extra-mental and Some mental event is an objective insight into the extra-mental, at the same time and in the same relation. The possible truth of naturalism is thus disproven by necessity. Lewis has much more to say, both in anticipating objections and in taking the next step from Naturalism’s inadequacies with reason to what this tells us about a Transcendent Mind. Before getting into that, we ought to bring in some different language to retrace our steps with even greater understanding. 

Moreland’s Composition in an Augustinian Key

Another version of this argument can be found in J. P. Moreland’s survey book on apologetics, Scaling the Secular City. The first obvious difference between the argument made by Lewis and the version of Moreland is that whereas the former used the word “Naturalism” the latter uses the word “Physicalism” to stand for the same. But immediately there is a second difference. Moreland defines and defends a view of human beings (of minds in particular) called dualism. This is the view that we are a composite of matter and mind: in other words, that the rational faculty cannot be reduced to molecules in motion. Additionally we should note that real dualism here will mean “substance dualism” and not simply “property dualism,” the former of which really believes that the mind and body are distinct, the latter that the body merely has a mind, but that the operations of this “mind” are really nothing more than the physiological-chemical effects of the body as a whole and never the efficient cause of anything in the world. In other words, property dualism is really mind-body physicalism [3].

At this point we will interject what Feser calls the “Augustinian proof” into Moreland’s line of reasoning because it contains a more clearly defined list. What Moreland does in this second step, and what the Augustinian proof sets forth, are four main abstract entities that (a) must have real existence for any view to be true and (b) cannot have real existence on the physicalist account. Those four abstract entities are 1. Universals, 2. Propositions, 3. Numbers (and other mathematical entities), and 4. Possible worlds [4]. More than this, each of these must exist preeminently in some way other than their changeable instances.   

Now we are ready for the third step, as well as the third difference between Moreland’s form and Lewis’ form. He cites the indiscernibility of identicals—i. e. “if ‘two’ things are identical, then whatever is true of the one is true of the other [and] … if something is true of the one which is not true of the other, then they are two things and not one” [5]. Building from this principle and an example, he then substitutes the relevant comparison of mind and brain (reduction of mind to body). Whatever property (P) is true of mind (M) must also be true of brain (B). Note that one cannot simply move from empiricism to physicalism. In other words, the physicalist has not only to show that all mental events in mind (M) and brain (B) are inseparable, but that they are identical. It is only if the set of all properties in M are identical to the set of all properties in B that the reduction can be reasonably maintained. The criterion thus established, Moreland is ready for his fourth step. 

He begins not with what mental events possess that physical events do not, but with what physical events possess that mental events do not. One might suppose such events to have size, weight, and location, for example (in the brain); but this is to miss the point. One’s idea of this room is neither fifteen feet wide, eight feet high, nor even bound to this room. Nor when we think of a basketball do our ideas, nor any part of our brain, turn orange, round, or bouncy. This alone shows that mental events and the physical properties to which they correspond are fundamentally different. He adds the experience of consciousness (first-person subjectivity) and private access to one’s own mental states for good measure. The only thing we need to notice about these has been captured by skeptical philosopher Thomas Nagel,

If physicalism is to be defended, the phenomenological features [the sounds, colors, smells, tastes of experience that make the experience what it is] must themselves be given a physical account. But when we examine their subjective character it seems that such a result is impossible. The reason is that every subjective phenomenon is essentially connected with a single point of view, and it seems inevitable that an objective, physical theory will abandon that point of view [6].

Returning to Feser’s Augustinian proof, those four abstract entities—1. Universals, 2. Propositions, 3. Numbers (and other mathematical entities), and 4. Possible worlds—have only had three candidates as to their real existence. There are Platonic realism, Aristotelian realism, and Thomistic realism. The first two have problems. Both Plato’s and Aristotle’s brand land in insurmountable difficulties. Platonic realism cannot explain how the “Forms” cause their instantiation in the world (and it moves the problem of the One and the Many up from time to eternity anyway); whereas Aristotelian realism leaves the predicates and properties of individual substances as their own cause (the form always being in its matter) and each bearing a wholly equivocal relationship to all other tokens supposedly in their type. “Green” would have to mean something different not only between a blade of grass and a Boston Celtics jersey, but between each and every blade of grass! What both causes and unifies every instance must be both 1. one for each universal and 2. solely in a mind. Feser adds to this that the unity must be so based upon the principle of proportionate causality [7]: namely that the effect must be, in some way, in its cause. 

An Evolutionary Objection

But surely even the Naturalist believes in logic and objective knowledge! Perhaps we might resurrect his case by placing the burden back on the Supernaturalist. Are not logical inferences with their antecedents and consequents really just causal events? One comes before the other in our minds. What is the real difference? Lewis says that, yes, ground-consequent is a species of cause and effect, but of “a special sort” [8]. Ground-consequent and cause-effect operate simultaneously as the same mental acts. However, remember Moreland’s principle of he indiscernibility of identicals—i. e. “if ‘two’ things are identical, then whatever is true of the one is true of the other [and] … if something is true of the one which is not true of the other, then they are two things and not one” [9]. Mere events are not “about” anything and are thus neither true nor false. “B followed A in my thoughts” and “B follows A necessarily” are a world apart. The first is an event, and may be inevitable, but the second, while also event, is, in addition, assigned a truth value in logic.

An epistemological argument can be grounded in one of those two fundamental principles mentioned by Geisler: logic in all possible worlds. At this point, the skeptic has a reply. If reason evolved, then although all worlds with truth claims require logic and therefore mind, it does not follow that all worlds require truth claims. But if there is a possible world (say the actual pre-rational world of this world’s past) without truth claims, then it follows that there is a possible world without logic. Here is where we bring Lewis back in. In the first place, natural selection is still only descriptive, so that what is true in supposedly “pre-rational” evolutionary history must still hold today.

In other words, it is not simply that reason could not have evolved from non-reason, but that the evolutionary definition of reason makes reason impossible still today. Within Naturalism, the principle of natural selection is merely the description of the process by which survival traits are rewarded with the fruit of their tendency.

Again, mental events cannot be an exception. As to how a survival trait becomes a genuine insight (here and now) natural selection is dumb and mute. We cannot call “valid” and “sound” those ideas that are really nothing more that more “fit” for survival. Moreover, as Armand Maurer said about the historicization of truth: “it must have come into existence as a part of man’s process of self-awareness and self-making, and hence it is relative to his situation in a certain moment in history … it must be historically relative, not timeless and supracultural” [10]. In other words, it is not merely theoretically possible, but necessary, that the “truth” in one moment is “false” in another, and vice-versa, and not only by units of time but in differing evolutionary strands and situations. What we call “true” would have to be relative to each of these evolutionary angles, which becomes something that no one would mean by “truth.” What we call “truth” today may be more evolved than that of our ancestors; but on that account, so will the more evolved truth centuries off into the future. Hence there no reason to call any truth on that progress "the way that things are” outside of our minds.

Lewis continued by examining the relationship between reason and nature. We may recall that the other debate concerning mind-body dualism is not simply whether or not they are distinct entities, but also how the one is causally related to the other. At the “frontier,” Lewis says, there is one-way traffic: “Nature can only raid Reason to kill; but Reason can invade Nature to take prisoners and even to colonize” [11]. Nature may alter reason, but only in an unnatural way: disease, injury, etc. And he eventually lands on Reason as the rightful king and Nature the original subject. We can start to see how this moves us closer to a Mental Event, or a Reasoning Agent, above and beyond the world. Indeed that is already true of every human being. Lewis adds that, “Reasoning doesn’t ‘happen to’ us: we do it” [12]. All aspects of human culture demonstrate this every day. We are, as Aristotle said, not merely the rational animal, but also the actor: man is a rational doer, and the doing is done first by his reason. So there is a sense in which reason is independent of nature: man independent of the cosmos, acting upon the cosmos.

On the other hand, unless any of our mental states are eternal and infinite and unchanging, our every act of reason is not only causal but requires a cause. So we have the independence and dependence of reason. Independent of mere matter; but dependent on what? The answer is reason. Consider that every consequent requires an antecedent for the inference to be drawn. This is true whether we are moving a priori or a posteriori, whether we are using induction or deduction.

Lewis concludes that “It seems … human thought is not God’s but God-kindled” [13]. He does so on the ground that there must be a Mind that never sleeps nor slumbers, so to speak, as all true propositions must be ever and always true. But the subsistence of truth requires a Mind that beholds it.

Now since Lewis’ book is not really about such a proof, he never follows through as thoroughly on this thought as we might like. He was only clearing philosophical ground for the evidential matter of investigating miracles. We must take the baton from him.

Following Through on Demonstration

There are really two ways to simplify this final step, which Feser really does a better job with, in his Augustinian proof. Speaking for my own method, I would first insist that we consider whether any true proposition could ever change in its truth value (true or false)? The burden of proof would seem to be on anyone to at least explain what this “change” could mean. On the surface we might suppose, with Hume, that since the non-existence of any particular thing implies no contradiction, then it follows that there is a sense in which all truth values are relative to the existence of their corresponding referent in the universe. Before x came to be and after x passes out of existence, or that given state, then there is no use in speaking about the “truth” of that object or state of affairs. But this line of reasoning proves too much: namely, that the proposition was actually never true. For what is the opposite of “never” but “ever,” such that there was at least “one point” on the space-time continuum at which said x was the case. But this “point” — was it divisible or no? Did every single property constituting that being pause and smile for the cosmic polaroid? No.

In fact, no such physical object or state of affairs, as the ground of truth, has ever or could ever exist. Thus if the truth of propositions were reduced to space-time phenomena, then they would be as divisible and mutable as their referents. 

There is one more way to see the same thing. Let us bring back our elephant with those six blindfolded men from that tiresome parable. Now let us play along and agree that our seventh man who first told the story is likewise “blindfolded.” He at least doesn’t see the whole. Perhaps we have seen the picture of the duck-rabbit. With the picture turned one way it is a rabbit, and turned the other it is a duck. We drew the lesson that we cannot rationally say that one cannot know some truth unless one knows every truth. The duck-rabbit turns out not to split reality into two, but only unites two species under one genus. There was a third idea that we keep calling “the duck-rabbit.” On the other hand, we may notice that if the question is “the whole elephant” or “the whole perspective,” each relational truth about the whole is in fact true.

But truth is a quality of mind and the principles of mind. Which mind has no blindfold. Each new observer around the elephant may add this or that new perspective that increases the members of our set of truths. Each truth is related to antecedents: truths which must be true in order for the added truth to be true. Each truth must be grounded in another or many others, and so on. But this process of antecedents cannot go on to infinity. And without the prior reason, no rational consequence would be known. Nor could any of these truths (whether antecedent or consequent) have become true nor cease to be true, for the reasons already covered.

Thus each truth must be beheld by a Mind in such a way that none of the truths ever change. But in order for such a Mind to behold all of these truths in this way, that Mind must likewise be unchanging and eternal. 

In anticipation of objectors asserting some alternative super-intelligence of infinite duration, whether angels, aliens, or “architects,” Feser shows why necessary truths require an “intellect which exists in an absolutely necessary way, an intellect which could not possibly have not existed” [14]. Otherwise, in principle, the universal, proposition, mathematical entity, or possible world, could be grounded in some other being: which would only move all the same problems for the physicalist one step sideways. 

_________________________

1. C. S. Lewis, Miracles (New York: Simon & Schuster, 1996), 20.

2. Lewis, Miracles, 23-24.

3. J. P. Moreland, Scaling the Secular City (Grand Rapids: Baker Books, 1987), 80.

4. Ed Feser, Five Proofs of the Existence of God (San Francisco: Ignatius, 2017), 87-90.

5. Moreland, Scaling the Secular City, 83.

6. Thomas Nagel, quoted in Moreland, Scaling the Secular City, 86.

7. Feser, Five Proofs, 209.

8. Lewis, Miracles, 27.

9. Moreland, Scaling the Secular City, 83.

10. Armand Maurer, quoted in E. L. Mascall, The Openness of Being (Philadelphia: Westminster Press, 1971), 129.

11. Lewis, Miracles, 37.

12. Lewis, Miracles, 41.

13. Lewis, Miracles, 41.

14. Feser, Five Proofs, 104.