Hart's version of natural law is empirical. His position is based on a theory of human nature which believes in certain truisms. For example, Hart believes that one truism of human nature is that the overwhelming majority of human beings wish to survive; in other words they would rather live than die If we wish to survive, it is imperative that a society be developed which will help ensure survival. Hart believes there are five features of the human condition which sometimes work against survival, and the legal system must take these into account.