Mere Christianity, Chapter 3

In Chapter 3 CS Lewis continues to try to explain and build up an understanding in our minds of his take on the law of nature. He points out that laws for the physical world are simply descriptive - they simply describe what things do, whereas his law describes what people ought to do. He supposes that because this law exists, there must be something beyond the facts of what people do. 

He anticipates that there will be arguments with this point from people who want to keep the natural law within the facts of observable behavior.  Such people will say that wrong action is wrong because it inconveniences us; or they will say that what is right isn't decided by what benefits one person, but what benefits humanity. He tries to show fallacies in each of these arguments, concluding that in each case, one is left with the statement that "Men ought to be unselfish."

Now, I'm not going to say that these arguments are right and he is wrong. In my previous post I outlined what I thought was a good description of the law of nature, as it explained why moral confict exists, and describes what people do. His idea is different, and that is all there is to it. 

What I do find interesting is his argument against the idea that what right is not simply what benefits humanity. He writes:

"Human beings, after all, have some sense; they see that you cannot have any real safety or happiness except in a society where everyone plays fair, and it is because they see this that they try to behave decently." 

Interesting way of putting forth the argument. He gives people more credit that I had expected, believing that people would spontaneously see what life would be like if everyone were good. I have difficulty seeing that image, even when described to me, and I'm a bit skeptical that every average person who behaves decently does so because they see that image.

To me, a much more likely approach to the 'greater good of humanity' argument is to take a page from economics, and argue that people will be good as long as the benefits of good behavior outweigh the price of that behavior. They put a little bit in and get more out, as it were.