There are three central issues here: Is there a universal or objective morality? Does it have a religious foundation? How can it be known? We are accustomed to speaking of the scientific laws of nature. It’s worth asking if there are moral laws of human nature. Many of us are the unwitting heirs to a philosophy that denies objective morality. We hold that science is objective, but values are subjective. We believe we can know scientific things but morality is a matter of mere opinion. On this basis we say things like “don’t impose your beliefs on me” while it would never occur to us to say “don’t impose your algebra on me.” Yet have we considered the possibility that there are moral laws in nature that are no less reliable and comprehensible than scientific laws?
Humans are unique in many ways, but mostly in the fact that we are moral beings. More than language, more than rationality, it is our moral nature that distinguishes humanity from even our closest animal relatives. Primatologist Frans de Waal, who studies chimpanzees and has done much to emphasize their close kinship with humans, admits that morality is something chimps don’t have. “It is hard to believe that animals weigh their own interests against the rights of others, that they develop a vision of the greater good of society, or that they feel lifelong guilt about something that they should not have done.” We can say to Bonzo, “You shouldn’t have done that” and “Bad chimpanzee!” but those are our own ways of speaking. We have no grounds to believe that chimps feel that way.
This distinction between chimps and humans points to a deeper chasm that separates human beings from the rest of the universe. All other objects, living and nonliving, function according to physical or scientific laws. Dangle a meaty bone in front of a dog and, no matter how much it has just eaten, it goes for the bone. Its response is a product ofseemingly uncontrollable instinct. Place a large stone on a slanted hillside, and it will automatically roll down. It has no choice in the matter. It is simply obeying physical laws.
But human beings are not like this. Human beings live in two worlds, the physical domain and the moral domain. If a person insults your mother, you respond, “You shouldn’t have done that.” When a friend tells you he deceived his business partners or family, you tell him he shouldn’t have lied. These normative statements are fundamentally different from physical laws. It makes no sense to say that the earth ought to revolve around the sun or that it would be unfair if it didn’t. A law of nature may be true or false, but it cannot be broken. As Carl Sagan puts it, “Nature … arranges things so that its prohibitions are impossible to transgress.”
There are parts of our human nature that operate according to these descriptive natural laws. If you tickle me, I will laugh. If either of us eats contaminated food, it will upset our stomachs. If we are dropped from a tall tower, we will plummet to the ground. These are the laws of physics and chemistry working on us, and we have no choice in the matter. On the other hand, there is a part of our human nature that is not descriptive but prescriptive. The simple proof of this is that moral norms and precepts, unlike natural laws, can be violated.
Honor thy father and mother. Thou shalt not murder. Thou shalt not covet thy neighbor’s goods. None of these commandments would make any sense if we had no option. But there is more. When we humans invoke the language of morals—praising and blaming, approving and disapproving, applauding and scorning—we appeal to a shared standard of judgment external to ourselves. Let us call this standard the natural law or the moral law. It differs from the scientific laws of nature in that it tells us not what we do but what we ought to do. Consequently we are free to break these laws in a way that we are not free to violate the laws of gravity.
