Cultural interpretations of behavior need never deny that a physiological element is also involved. Such a denial is based on a misunderstanding of scientific explanations. Biology did not deny chemistry, though chemistry is not adequate to explain biological phenomena. Nor is biology obliged to work according to chemical formulae because it recognizes that the laws of chemistry underlie the facts it analyzes. In every field of science it is necessary to stress the laws and sequences that most adequately explain the situations under observation and nevertheless to insist that other elements are present, though they can be shown not to have had crucial importance in the final result. To point out, therefore, that the biological bases of cultural behavior in mankind are for the most part irrelevant is not to deny that they are present. It is merely to stress the fact that the historical factors are dynamic.