When Things Stop Making Sense

A philosoramble in which I present a classic critique of materialism, namely, that if materialism is true, then we cannot have any knowledge. This presentation develops upon the work of C S Lewis1 and Alvin Plantinga.2 These arguments have also been considered by such diverse minds as Blaise Pascal,3 Charles Darwin,4 G K Chester­ton,5 J B S Haldane,6 and Thomas Nagel.7

One day, when most of the philosophers were out at tea, or perhaps tucked up in bed with Critique of Pure Reason and a handful of aspirin, there was a great accident in the philoso­phy of mind department. Some absent-minded scholar must have slipped up somewhere, and, of course, the press went for the jugular at once, for the next day, all the papers were chock full of great blundering misreports that science had at last explained all the secrets of love and happiness and the human mind, leaving the philosophers out of a job (once and for all) and feeling rather like those hapless fellows who once woke up in the middle of the night wondering what all the clamor was, why their houses were on fire, and above all, whose daft idea it was to let in the big wooden horse.

Hence, or thereabouts, materialism (which might also be called physicalism, naturalism, or reductionism) took hold of peo­ple’s minds and imaginations and became the prevailing phi­losophy of this scientific age.

Materialism is not the same thing as science. Rather, it is the much bolder philosophical claim that there is nothing at all outside of physical material reality. Roughly speaking, physics seeks to describe the universe as being built up from some basic substances (matter and energy) which are gov­erned by a set of unchanging physical laws – this describes physical material reality. Materialism is the philosophy that this description could, in principle, account for everything that is. Furthermore, materialism claims a physical explana­tion is the only sort of explanation that can be given to ac­count for why anything happens.

The essence of the materialistic perspective is to take the scientific mindset and to magnify it into ultimate reality. For example, physics uses a “closed system” or an “isolated sys­tem” as the basic model for all of its reasoning. A closed system is one in which there are no outside influences; events have causes that are totally self-contained in the system. This is the foundational assumption on which physical models of the universe are built. Now materialism is the sweeping philo­sophical suggestion that our universe, at bottom, is a closed system. Within the framework of a closed system, physics hopes to build up a description of what will happen by ex­trapolating from what has already happened. The belief of materialism is that things are fundamentally “built up” this way, from little pieces pushed around by big laws. Physics ob­serves an underlying mathematical orderliness in the nature of things; materialism asserts that this order is in some way responsible for governing the things themselves. In material­ism, there is no such thing as “outside intervention.” There are no surprises. There are no “miracles.” If it makes any sense at all to ask why something happened a certain way, the only possible answer for the materialist is, “Because it had certain physical causes that made it happen that way.” (But see the Quantum Endnote [8].) This is the materialistic vision.

At the very least, I hope to convince you that the phi­losophy of materialism is not at all obvious, and should not be accepted unquestioningly. After all, why should electrons go whizzing around subject to mysterious mathematical laws? What are these laws anyway? Where did they come from? And, what are the laws made of? (Remember that in a mate­rialistic philosophy this is the first and most sensible question that we should ask.) Are they made of matter? Are they globs of energy? If they are neither of these things, then what? Materialism does not admit the existence of the immaterial. Are the laws themselves an “outside influence” on the system, contradicting materialism’s assumption that there are no out­side influences?

But we will pass over these questions, and instead turn our skepticism to a matter of more personal importance: if materialism is true, then what does that say about my own mind? What would it mean if everything, from the workings of my mind to every thought that I think, could be completely explained by physical causes?

There are many, many issues which could be raised at this point, including those of free will, ethics, and the self, but for now we will concentrate on just one problem, though perhaps the most fundamental of them all. I will argue that materialism destroys the dearest treasure of all philosophers and scientists alike: namely, knowledge itself. We call this the Argument From Reason: materialism excludes the possibility of us having any knowledge.

To begin with, we define “knowledge” according to the philosophical notion of justified true belief. For something to be knowledge, (1) I must believe it, (2) it must be true, and (3) I must have some reason to believe it. This last criterion will be the most important for this discussion. There are many pos­sible reasons for my belief, such as “because I see it right in front of me,” or “because my experience tells me that it is so,” or “because my trustworthy friend told me so”. But, I must have some reason to believe.

Let us review the basic ideas of materialism: (a) every­thing that exists could, in principle, be explained by physi­cal material causes, and furthermore, (b) the only sort of explanation that can be given for why anything happens is a physical explanation.

With this in mind, let us now consider knowledge in light of materialism. If materialism is true, then by premise (a), there is in principle a physical explanation or a physical material “cause” for these thoughts. To the materialist, my thoughts are the consequence of some immensely complicated chemi­cal butterfly-effect resulting from all the stimuli my body has been exposed to over my lifetime. Moreover, the only sort of “cause” my thoughts can have is the physical, material vari­ety. There is nothing else governing my thoughts, since from the materialist perspective there is no other sort of causation. That’s all. Every thought of mine would have to be entirely automatic, programmed into me by the laws of physics.8

Here, then, is my central argument. If physics, and phys­ics alone, completely governs my thoughts, then I say there is no reason to believe my thoughts ought to be true because the physical explanation for a thought makes no reference to the logical truth of those thoughts. The physical explana­tion deals with electrons and quarks and the Higgs boson. But how can we get from these physical things to the logical truth of a statement? In real life, we don’t see any connection between physical causation and logical truth. Quite the op­posite: it is perfectly possible to give a physical explanation for a logically false thought. It doesn’t break the laws of physics for me to think, “I am a Martian.” Perhaps I have taken LSD and have become quite convinced that I am a Martian. The laws of physics allowed this to happen. The question, then, is why I should believe that any thoughts I am currently having are true ones. For if materialism is true, then any allegedly true thoughts of mine – say, “I had pancakes for breakfast” – laws that produced the false thought “I am a Martian”. You will surely object that I was on LSD when I thought I was a Martian; thus, that thought was just the result of some wacky chemical reaction. But that’s exactly the point. To the materialist, my mind is always “on drugs,” if we take “drugs” to mean chemical substances of one sort or another. To the materialist, my thoughts consist entirely of “wacky chemical reactions,” and that’s it. Why, then, should there be any reason why we would get logi­cal truth out of a chemical reaction?

This understanding of thoughts is disastrous since, to the materialist, the only acceptable sort of explana­tion for anything is a physical explanation (according to premise (b)). So if physics does not provide reasonable justification for the truth of our thoughts, then the mate­rialist has nothing left to stand on. There can be no way of separating true thoughts from false ones, for there is nothing but physical laws. Even the laws of logic them­selves would be nothing more than arbitrary beliefs pro­duced in us as a consequence of blind physical laws. Thus, if we have no reason to believe that any of our thoughts are true, we cannot have any knowledge.

At this point, the critical reader might respond, “Per­haps I can’t prove beyond a shadow of a doubt that my mind is telling me the truth, but I can still have knowledge. For in my experience, certain beliefs have always worked. They are consistent with one another; they have withstood whatever tests or experiments I have performed; they have kept me alive and well fed thus far; what further reason do I need to believe them?”

The idea that my beliefs ought to be trustworthy because they keep me alive is expressed in its strongest form as the Evolu­tionary Argument. This argument proposes that we can justify our beliefs, even if they are completely explained by physical causes, by appealing to natural selection: (i) our minds are at least partially governed by our genes; (ii) over time, the effect of natural selection on a population is to increase the frequen­cy of genes that confer an increased likelihood of survival and reproduction; (iii) having a mind whose thoughts accurately reflect the external world confers a survival and reproduc­tive advantage; (iv) therefore, I do have reason to believe my thoughts are probably true, and better yet, I have a mechanism by which truth could emerge from pure physics.

I see two main weaknesses in the Evolutionary Argument. The first is based upon the general principle that we should be very cautious before proposing that evolution necessarily approaches any kind of end goal. Evolution is random. Why, then, should evolution select for the ability to think logically true thoughts – or the ability to think at all, for that matter? Evolution selects for survival and reproductive ability alone. So, there is no reason at all to suppose that a mind capable of thinking logically true thoughts is in any way a necessary end product of evolution, nor even a probable one. Extremophile bacteria like Deinococcus radiodurans, which can survive nuclear fallout and the vacuum of space, would probably consider themselves much better adapted for survival and reproduc­tion than any Homo sapiens – if they could think, that is. For this reason, it is a very unhelpful misuse of language that we say that humans are the most “highly evolved” species on the planet. This is just anthropocentrism. In the strict sense, every living species is just as “highly evolved” as every other species, since every species comes from an equally long evolutionary lineage, tracing back to the very first cell (if we believe in a single origin of life). Every creature that survives can con­sider itself a winner in the evolutionary struggle for exis­tence, the bacterium and the nematode just as much as the ape. So we conclude that there is no reason to believe that the evolutionary process tends towards complex minds or true thoughts, except by coincidence alone.

It will be objected that we have only contrasted animals with complex minds (“minded” animals) with mindless ones. We have not given any examples of how an animal whose thoughts fundamentally misrepresent the world could pos­sibly compete with an animal that thinks true thoughts. Yet in reply, I would say that materialism sees no distinction be­tween minded and mindless animals. The materialistic mind is, at bottom, automatic. Moreover, our subjective experience of the world is irrelevant to natural selection; the only thing that matters is how an organism responds to its environment. It is not essential that the animal should be aware of what it is doing, or why it is doing it, just as long as it stays alive and keeps reproducing. Bacteria and beetles and the roaches in Dunster House can survive on “autopilot.” So combining all these ideas, we can imagine an animal whose thoughts are completely meaningless, even false, but whose instincts are accurate enough to keep it alive. What evolutionary reason is there to suppose that we are any different from this animal? You may say that our thoughts affect our decisions, but this presupposes a certain notion of free will which most materi materi­alists would deny. These questions cannot be answered fully here, but it suffices to say that in the materialistic vision, the accuracy of human thought is not at all assured.

The second weakness in the Evolutionary Argument is that even if there were significant selective pressures favoring a complex mind, natural selection could never select for the truth or falsity of any individual thought; it could only select for genes that promote thought patterns advantageous to survival and reproduction. Unless the geneticists manage to uncover a strong connection between the expression of certain genes and the possession of certain true beliefs, the Evolutionary Argument cannot give me a reason to believe any particular thought of mine is true. At best, we might be able to say that a belief of mine shows useful cognitive abilities (like abstract reasoning, or pattern recognition), which could have a genetic origin and could also have survival and reproductive advan­tages. Yet the truth or falsity of the belief itself – whether it be Copernicus’s heliocentric model of the universe, or Ein­stein’s theory of relativity, or Christianity, or the philosophy of materialism – offers us no evolutionary advantage whatso­ever. Even though we might be capable of knowing the truth about the most basic observable facts, such as “1+1=2” or “there is a horde of Dunster roaches chasing me,” we couldn’t be certain that we know the truth about many of the ideas most important to us.

All this being granted, the materialist might raise another kind of criticism: has our skepticism spiraled out of control? Can the non-materialist propose any philosophically rigorous basis for knowledge that meets his own standards of skepti­cism? This is something of a digression, and does not directly refute the original argument, but I think it is a very reason­able digression. In response, I think that the non-materialist is in a much better position than the materialist, since the non-materialist at least does not contradict himself. To the non-materialist, there is plenty of room left for an immaterial mind capable of real knowledge. Materialism, on the other hand, is a very restrictive philosophy: it presents an affirmative vision of a world where the immaterial mind does not exist.

There is one final move the materialist could make at this point: “So what?” Even if all these arguments are sound, and materialism is self-defeating, and there truly can be no knowledge in this world: so what? Maybe the world is like that. Maybe there is no reason to believe the thoughts of my mind. Then what? Who can argue against the man who does not be­lieve in truth? It must be noted that this is no longer a defense of materialism but an entirely different philosophy, namely, total skepticism.9 I don’t think that materialists are total skeptics, and if they are, then they are certainly no longer materialists. But perhaps this is the topic for another philosoramble.

This concludes our brief sketch of the Argument From Reason and its counterarguments. We have argued that ma­terialism must be rejected because a materialistic mind does not allow the possibility of human knowledge, and therefore contradicts even itself as a way of knowing and understand­ing the world. Yet it feels as though we still have a long way to go before we can save Reason. Where do we go from here? If we allow the possibility of an immaterial objective reality, then how can we approach such a reality? What is it? What’s it like? How can we understand it? Could Christianity truly account for the frustration of the human condition, in which we are creatures undeniably bound up in the material world, influ­enced and conditioned by the everyday material realities that we see and hear, everyday realities which so often don’t make sense? And could Christianity explain the hope of the hu­man condition, that we have something like Reason (though we so often choose not to follow our Reason), and Freedom (though we so often cling to those things that only diminish that Freedom), and Self (though we hopelessly misunderstand our Selves as being meant for Selfishness)? A central theme of the Christian faith is that God promises that those who seek Him with all their heart shall find not only their Freedom (Gal 5:1) and their Self (Eph 4:24), but also a firm basis for Reason and Knowledge (Col 2:2-3). If we seek to redeem Reason, the solution is not to resort to material skepticism, but to rely upon the God who supports and redeems all cre­ation – the God who sent wisdom and reason to us, taking on the flesh and form of a man in his son Jesus Christ.


[1]. C S Lewis, Miracles. Macmillan (1978). This argument is found in Chapter 3, “The Cardinal Difficulty of Naturalism.”

[2]. Blaise Pascal, Pensées, #72: “For it is impossible that our rational part should be other than spiritual; and if any one maintain that we are simply corporeal, this would far more exclude us from the knowledge of things, there being nothing so inconceivable as to say that matter knows itself. It is impossible to imagine how it should know itself. So, if we are simply material, we can know nothing at all; … Hence it comes that almost all philosophers have confused ideas of things, and speak of material things in spiritual terms, and of spiritual things in material terms.”

[3]. Correspondence of Charles Darwin to William Graham (July 3, 1881), acces­sible online at http://www.darwinproject.ac.uk/entry-13230: “Nevertheless you have expressed my inward conviction, though far more vividly and clearly than I could have done, that the Universe is not the result of chance. But then with me the horrid doubt always arises whether the convictions of man’s mind, which has been developed from the mind of the lower animals, are of any value or at all trustworthy. Would any one trust in the convictions of a monkey’s mind, if there are any convic­tions in such a mind?”

[4]. G. K. Chesterton, Orthodoxy, p.25: “That peril is that the human intellect is free to destroy itself… It is idle to talk always of the alternative of reason and faith. It is an act of faith to assert that our thoughts have any relation to reality at all. If you are merely a skeptic, you must sooner or later ask yourself the question, ‘Why should anything go right; even observation and deduction? Why should not good logic be as misleading as bad logic? They are both movements in the brain of a bewildered ape?’ ”

[5]. J B S Haldane, Possible Worlds and Other Essays, p.209

[6]. Alvin Plantinga, Where the Conflict Really Lies: Science, Religion, and Naturalism. Ox­ford University Press, USA (December 9, 2011).

[7.] Thomas Nagel, Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False. Oxford University Press, USA (September 26, 2012).

[8]. In speaking of “physical causes”, I should not presuppose that the universe is deterministic. Quantum mechanics complicates things by suggesting that we live in a universe governed by probabilities, where the events themselves are truly ran­dom, not having any deterministic “cause” at all. I don’t see this as a major flaw in the argument. True randomness does not seem like a very secure basis for human knowledge. There is also the question of what we really mean by “randomness”. If there is a wavefunction specifying the probability of certain events happening, then we might argue that that is already a certain level of structure (why were the probabilities set to those values?) which could hesitantly be regarded as a physical “cause” or “explanation” for an event in the sense of this article. However, since I am admittedly unfamiliar with quantum theory, I will set this topic aside for now.

[9]. I am using the non-standard phrase “total skepticism” to mean philosophical skepticism (whether Academic or Pyrrhonian), to distinguish it from the everyday sense of the word. The Stanford Encyclopedia of Philosophy, available online at http://plato.stanford.edu, provides a helpful introduction to this topic, and is a great resource in general.

Stephen Mackereth ’15 is a mathematics concentrator in Mather House.

Tags: , , , , , , , , , , , , , , , , , ,