the conception is not taken as an hypothesis demanding proof or contradiction, but as a fiction accepted without question. In the one case, man is humble about his beliefs, because he knows they are tentative and incomplete; in the other he is dogmatic, because his belief is a completed myth. The moralist who submits to the scientific discipline knows that though he does not know everything, he is in the way of knowing something; the dogmatist, using a myth, believes himself to share part of the insight of omniscience, though he lacks the criteria by which to tell truth from error. For the distinguishing mark of a myth is that truth and error, fact and fable, report and fantasy, are all on the same plane of credibility.
The myth is, then, not necessarily false. It might happen to be wholly true. It may happen to be partly true. If it has affected human conduct a long time, it is almost certain to contain much that is profoundly and importantly true. What a myth never contains is the critical power to separate its truths from its errors. For that power comes only by realizing that no human opinion, whatever its supposed origin, is too exalted for the test of evidence, that every opinion is only somebody's opinion. And if you ask why the test of evidence is preferable to any other, there is no answer unless you are willing to use the test in order to test it.
4
The statement is, I think, susceptible of overwhelming proof, that moral codes assume a particular view of the facts. Under the term moral codes I include all kinds: personal, family, economic, professional, legal, patriotic, international. At the center of each there is a pattern of stereotypes about psychology, sociology, and history. The same view of human nature, institutions or tradition rarely persists through all our codes. Compare, for example, the economic and the patriotic codes. There is a war supposed to affect all alike. Two men are partners in business. One enlists, the other takes a war contract. The soldier sacrifices