C.S. Lewis starts his argument for the existence, and even expectation, of miracles by noting that before one can evaluate whether a miracle happened, one needs to decide whether miracles can happen. He observes that the author of one Bible commentary dates the Gospel of John as after Peter’s execution, because in it Jesus predicts how Peter will die. To require a date after Peter’s death makes the implicit assumption that predictions are not possible. Likewise, if we look at claimed Christian miracles with the assumption that miracles cannot happen, we will not actually be properly evaluating the miracle, because we already presupposed that it cannot happen. So Lewis’ purpose in the book is to answer the question of whether miracles can happen, not to discuss any of the historically claimed miracles (other than the essential miracle of Jesus’ resurrection).

There are really only two views about the nature of reality. One is Naturalism, which says that Nature (whatever that looks like) is all there is; Nature is the essential Fact that exists on its own. The other is Supernaturalism, which says that something outside of nature is the essential Fact. Naturalism does not assume that there is no God, but any naturalistic God must be a sort of emergent property of nature, an God-is-everything sort of pantheism. This is quite opposed to Supernaturalism, which says that God created nature.

The first task is to choose between Naturalism and Supernaturalism, since if Naturalism is true, then obviously miracles must be explainable in terms of the whole system, and hence, not what we normally mean by miracles would not exist. Lewis notes that all knowledge requires that reasoning is actually able to perceive correctly what is happening outside our minds. Hence, any theory must make it possible to reason (otherwise, there is no science and no knowledge, and therefore we cannot make any conclusions about the nature of reality). Haldane observes that the Materialism version of Naturalism does not admit any ability to reason: “If my mental processes are determined wholly by the motions of atoms in my brain, I have no reason to suppose that my beliefs are true ... and hence I have no reason for supposing my brain to be composed of atoms.” (p. 22, quoting Possible Worlds, p. 209). Generalized Naturalism still has the same problem. Reasoning involves saying that B must be true because of A. However, this involves two thoughts, which are events, and ordinary events have no causal relationship. Somehow these events of thinking must be related; we have to have perceived some truth, not merely had a thought event. Arguing that we perceive truth to by being conditioned to expect something is not sufficient, as there are plenty of examples where the normal expectation fails in some circumstances. For example, water boils at 100 °C—except when you try it on a high mountain. Furthermore, Naturalism provides no mechanism for the emergence of rational creatures. Evolution is simply improving responses to stimuli, but as we have seen, there is no relationship between a non-rational response to outside stimuli and a rational perception of the nature of the outside, no matter how much time and how many mutations happen. Understanding a machine is connected to the machine, but is obviously not a part of it. So, while Naturalists and Supernaturalists both agree that we do reason, Naturalists are at a loss as how to explain it.

It seems, then, that Nature has things happen to her, namely reasonings. We have seen that Reason cannot be contained within Nature, so it must somehow come from outside, which means that Naturalism is out of the question. We can observe that since our Reason is interrupted every night by sleep, and that sometimes our reasoning is incorrect, that our reasoning cannot be God’s, and is probably God-kindled. In fact, Reason mixes quite well with our natural stimuli (sensations, emotions, etc.) and even gives them higher purpose, yet when our physical state dominates our thinking, Reason is destroyed. So it seems that the supernatural invasion of Nature seems intended to fulfill Nature.

A similar argument against Naturalism is that humans consistently make moral judgements, that it is obvious that we ought to behave in a certain way. This implicitly assumes that there is an underlying truth, but that is inconsistent with Naturalism—if we are simply the product of the system and all our thoughts are a product of the system, then there is no basis for an ought-to. However we act is a product of the system and is okay. It would be consistent to take a viewpoint that there is no such thing as morality, but Naturalists rarely do so. While they reject traditional reasons for morality, they give reasons like it is good for society. Well, if it is really better (and what does that mean if there is no objective truth?), then Nature would have evolved us to do it. So if we admit a morality, or a “better,” then we, by necessity, admit that there is something outside of Nature.

One might object that if the supernatural exists, it should be obvious. Actually, for most of history, and outside of Western culture still, people were quite familiar with the supernatural. Science, in assuming that Nature is not invaded, has made us forget. Here Lewis raises an interesting possibility. Previously people simply followed the wisdom of a few mystics and sages, but now either humanity has made a huge mistake in rebelling against tradition, or since we all must now find the truth ourselves, that God is offering us the opportunity for all of us to become sages.

Lewis then turns to two specious arguments against miracles. First, that miracles are an explanation for unknown causes. However, you can only determine something is a miracle if you are familiar with the laws. Joseph was quite familiar with the law that babies are only produced via sex, so he intended to divorce Mary.  “God made me pregnant” is only a miracle if it is unusual, and it took an angelic visit to convince Joseph to go through with the marriage. The second argument is that the miracles were used in olden times when people thought the earth was the center of the universe, but now we know that the earth is a tiny, unimportant speck. This is false, since the ancient Greeks familiar with the fact that the universe was much larger than the earth, and it was accepted all through the Middle Ages. The thing is, both sides of this argument are used against Christianity: if the earth is a tiny speck in an empty universe, it is evidence that God doesn’t exist, but if the universe is full of things, it is also evidence against God. The problem is that modern men equate size with importance—a galaxy is more important than a planet. But we would not consider a tall man more important than a short one; we have applied a falsity to the universe.

Although we have established that there is a supernatural Fact, we have yet to establish that Nature was made in such a way as to permit its laws to be broken. The laws of nature describe how things happen if nothing acts on them. If I hit billiard balls, the laws of motion will describe how they roll, assuming no one bumps the table or removes a ball. But a miracle is Nature altered, so the laws of nature are irrelevant. Once the alteration occurs, the laws of nature take hold—wine miraculously created will get you drunk.

So miracles outside the laws of nature are possible, but are they probable? Hume, in Essays, argues that miracles are not probable because our experience finds them to not exist. This is a circular argument: in order for past observations to have any relevance for the future, Nature must always work the same way, but if everything including our thoughts is just a product of nature, there is no assurance that Nature will not work differently tomorrow; if the laws of nature are part of nature, then they may evolve. The only solution is for the laws of nature to be imposed upon Nature from the outside by a Creator. But if there is a Creator, then He can alter nature and thus cause miracles. In fact, it was the view of the constancy of God that led to the development of science in the first place; pantheistic cultures tend to view things as changing and cyclical.

The basic miracle in Christianity is the Incarnation, that is God, coming into Nature as a man. If it is true that the essential Fact entered Nature, then this should be the turning point of the entire story of Nature. When we observe Nature, we see a common pattern of descent in order to ascend: the seed dies in the ground and then becomes a tree; living beings reproduce by first joining sperm and ovum into a single-celled organism (descending to the lowest form of life) and then maturing into an adult. So is Christ just another Corn-king? The odd thing is that the annual death-rebirth cycle is only rarely mentioned in the Bible, and Christ came into a religious culture quite opposed to that thinking. Nor did the early Christians claim to be a corn-religion to escape persecution. It seems that Christ enacted the part of the Corn-king, but thought very differently; the annual death-rebirth cycle is not the object of worship, but is there because descending to reascend is the nature of God. The great is the servant of all.

Lewis makes an interesting observation on human nature: we make coarse jokes and we feel like death is somehow wrong. Coarse jokes center around our animality, and it is odd that we find coarse jokes either funny or uncouth if we are only animal. Dogs do not appear to find anything funny about being dogs, but we find it odd that we are animals. And in Naturalism, death is expected and natural; why should we think ghosts and dead people to be somehow wrong? It would seem that humans are something supernatural joined to a natural body, and that sometime long ago the spirit rebelled and lost control of the animal part. But in submitting to death, we can undo the rebellion and be lifted up by death of Jesus who died in our place, taking our punishment, and can thus raise us up.

Miracles are recorded outside of Christianity, and nothing in God as revealed by Christianity prevents Him from doing miracles through individual pagans. However, the miracles expounded by other religions have a nature that makes them unlikely—if the sorts of miracles you find among the Greek gods happened, it would be an invasion of nature, but a highly capricious one. The miracles ascribed to Buddha are unlikely because someone who taught that we need to escape from the illusion of nature would hardly doing things on the Natural level. However, the miracles in the New Testament seem to be in the same “style” as Nature has. “I contend that in all [the miracles of the Old Creation] the incarnate God does suddenly and locally something that God has done or will do in general.” (p. 219). God creates wine all the time; Jesus created it instantly. Every year God makes little seed into much seed, every year few fish turn into many fish; Jesus turns little bread and fish into a lot quickly to feed thousands. But note that when the devil suggests that Jesus turn stone into bread he refuses; God is not ordinarily in the habit of transmutation. Finally, in every conception God unites a sperm and an egg and a baby is created; “but once, and for a special purpose, He dispensed with that long line [of natural descendants] which is His instrument: once His life-giving finger touched a woman without passing through the ages of interlocked events. Once the great glove of Nature was taken off His hand,” (p. 225) for the purpose of creating a new kind of Man, the Man of Himself. The miracles of the New Testament have the same style as that which Nature is written in, which argues for their authenticity.

Miracles of the New Creation are of a completely different nature, yet have the flavor of extensions of Nature. The resurrected Christ is touchable and can eat, but can also come through locked doors and is often not immediately recognized. Some have argued that this was hallucination, but the hallucinations are so consistent between people, time, and places that it would have to be some equally miraculous shared hallucination. So it seems that the resurrected body has the character of the old body, but yet seems to function at a higher dimensionality. Other miracles of the New Creation suggest that the spirit can control nature in new ways: Jesus walks on water, and reverses the process of disorder when he raises Lazarus. It seems, then, that the New Creation that Jesus is making us into is a blending of spirit with nature; creating a centaur rather than simply a mounted knight as we were originally.

In Miracles, Lewis gives a thoughtful argument to the likelihood of miracles. The strength of his argument is in showing how Jesus’ miracles are of the same character as nature. They make the New Testament seem less fantastic and more like the surface narrative in a great story whose plot we only dimly glimpse. In fact, the miracles seem almost natural and expected.

The weakness of his argument is that Naturalism does not provide a possibility for the rational thought that we observe. He may be right, but I cannot follow the argument well enough that it necessarily follows. I like the argument, as a Christian, because it provides at least a partial explanation of what it means to be made in the image of God—to be able to perceive the machine as well as exist in it. However, it is not as compelling of an argument in and of itself. I find the observation that we make jokes about our animal nature and that we find death unnatural as the most telling arguments of the flaw in Naturalism. I wonder if a more compelling argument would be to argue that it is impossible to perceive the nature of something from inside of it; Flatlanders cannot perceive two-dimensionality unless some part of them is three dimensional.

Granting that Lewis’ argument of reason is acceptable, the rest of the book flows quite naturally, and as usual, paints a picture of God and the Christian life that is more mysterious, wonderful, and awesome than we tend to think. Something amazing is afoot, and Lewis gives us another glimpse of what it is.