Lewis contrasts the Moral Law with the natural laws that govern the physical world: The Moral Law, or the Law of Human Nature or Behavior, tells us how we ought to behave. The laws of physics, like the Law of Gravity, tell us how physical objects do behave.
Lewis argues that the Law of Human Nature/ Behavior or the Moral Law really exists. It’s objectively real. It exists independently from us. It is “out there” pressing upon us to behave in certain ways. We somehow just know it’s there. We did not invent it.
Lewis talks about another objection: The Moral Law is only “what pays” for us. He argues that this is not true. Decent behavior does not always pay. It may often be an inconvenient thing to do. But we feel compelled to do it nevertheless. The Moral Law “presses upon us” the obligation to do the decent thing, even if it may cause us discomfort.
Again, I agree with Lewis. The Moral Law is an objective reality that exists “out there” beyond us. It is independent of our opinions and personal preferences.
It is such a profound and awesome thought, isn’t it? To think that there exists in our world a law that is as real as the laws that govern the physical universe! The natural laws govern all the concrete objects that exists, but the Moral Law governs us – how we behave towards others, how we live our lives, and so on.
I love this quote:
“It begins to look as if we shall have to admit that there is more than one kind of reality; that, in this particular case, there is something above and beyond the ordinary facts of men’s behavior, and yet quite definitely real – a real law, which none of us made, but which we find pressing on us.”
It is such a powerful thing to realize that the material world is not all that there is. The physical universe is not all of reality. Beyond the natural world lies another reality. And here I am reminded of the Lion, the Witch and the Wardrobe: When the Pevensie siblings discovered the world of Narnia through the wardrobe, they discovered that Nature is not all that there is. There is a realm beyond the physical world where the supernatural exists. In this case, the reality of the Moral Law points to the existence of a moral realm.