Each chapter of C.S. Lewis’s Miracles is summarized below in roughly 500 characters, giving you a quick overview of the main points and arguments. Use the navigation links on the right to jump to a specific chapter summary.
The scope of this book
When we go to investigate claims about miracles, the philosophy (or worldview) we hold will determine what conclusions we’re willing to accept. A naturalist, for example, will always reach naturalistic conclusions. Thus the question of whether miracles have ever actually occurred must be put on hold until we’ve answered the more fundamental philosophical question of whether miracles are even possible. To just assume they are not would be to beg the question.
The naturalist and the supernaturalist
Naturalists believe nature (i.e., physical reality) is all that exists. If they are right, then miracles are obviously impossible. There can be no such thing as a supernatural event if there is nothing beyond nature to cause it.
Supernaturalists believe something else exists beyond nature. If they are right, then it is possible that nature could be interfered with from beyond. That is, miracles could possibly occur.
Thus whether miracles are possible depends on whether naturalism or supernaturalism is true.
The cardinal difficulty of naturalism
If naturalism is true, then every event must have a natural explanation. That is, everything (our thoughts included) must ultimately be a product of the physical, mechanistic laws which govern the contents of the universe.
But this picture of reality discredits reasoning. If our conclusions are physically caused by the mechanistic forces of nature, rather than freely and genuinely inferred, then their validity is called into question.1 Of course, this problem applies to all conclusions reached by reasoning, including the conclusion that naturalism is true.
By discrediting reason, naturalism discredits the only means by which it can be affirmed. Thus it is self-refuting.
Nature and supernature
It follows that reason, in some sense, is not natural. As Lewis puts it, ” … something beyond Nature operates whenever we reason.”2
There is a one-way relationship between nature and reason. Reason can positively modify nature for some purpose, but natural events can only destroy reason. A toothache, for example, disrupts the act of reasoning; it does not produce new insights.
Rational human minds must either exist on their own, or they must derive their power of rationality from some external source. A non-rational, natural source is ruled out. Our rationality is not self-existence; it is contingent, it came into being, and it is interrupted and flawed. It must, therefore, derive from some other rational, non-natural (or supernatural) source. And that source is God.
All of this goes to show that nature is not the extent of reality. There is something beyond nature that is rational, and that feeds rationality into nature through us.