The statement that norms are man-made (man-made not in the sense that they were consciously designed, but in the sense that men can judge and alter them—that is to say, in the sense that the responsibility for them is entirely ours) has often been misunderstood. Nearly all misunderstandings can be traced back to one fundamental misapprehension, namely, to the belief that ‘convention’ implies ‘arbitrariness’; that if we are free to choose any system of norms we like, then one system is just as good as any other.