The first section of Lewis’ Mere Christianity deals with the topic of “natural law” that I discussed in a recent post. Lewis refers to it as the “Law of Human Nature.” While some apologists, like William Paley, began their classic proofs of God with physical causation, Lewis prefers to deal with human behavior, using the “moral argument” to work back to the origins of man’s spiritual purpose and makeup. But without going quite that deep, I want to look at the idea of universal mores in human conduct. Lewis begins by pointing out that whenever people get into a dispute, they seek to justify their actions. Even if a person is clearly acting in self-interest, he will still phrase his explanation in a way that defers to a higher norm. “He is,” says Lewis, “appealing to some kind of standard of behaviour which he expects the other man to know about.” Lewis points out that this is quarrelling, not mere fighting. Animals do not quarrel. They do not discuss the right and wrong of the matter.
Now it is true that the “Law of Human Nature” is not like the law of gravity. Unlike the latter, a man is free to disobey this law, and frequently does. But does this disprove its existence or impact on human life? Lewis explains that long ago people referred to a moral norm as “natural” because they “thought that every one knew it by nature.” There might be exceptions, but “taking the race as a whole, they thought that the human idea of decent behaviour was obvious to everyone.”
Skeptics complain that ethics are subjective and vary from one culture to the next. Lewis says this is a straw-man argument. “There have been differences between their moralities, but these have never amounted to anything like a total difference.” He points out that certain moral themes can be found in every society. For example, no one can think of a culture where cowardice, selfishness or adultery are admired. People may make mistakes about the details, Lewis notes, but the overall concept of goodness remains an indelible part of the human conscience. As for the fact that people, even professedly moral individuals, fall short of pure virtue, does not undermine Lewis’ point. The moral law deals not with the facts of behavior, but how people ought to behave. Even our expressions of disappointment with ethical systems, or our outrage at moral hypocrisy, reinforce the notion of a higher standard to which we are all held.
Let me also add that I find it interesting to see a Protestant handle this subject, which is traditionally the domain of Catholic thinkers like Jacques Maritain (Lewis’ contemporary). Like the neo-Thomists, Lewis adopts the Aristotelian idea that evil is not something that is sought for its own sake but in the pursuit of something good. Wickedness lies in the fact that we desire a good in the wrong way or at the expense of a greater good.