In science, tradition is often used in the literature in order to define the relationship of an author's thoughts to that of his or her field. In 1948, philosopher of science Karl Popper suggested that there should be a "rational theory of tradition" applied to science which was fundamentally sociological. For Popper, each scientist who embarks on a certain research trend inherits the tradition of the scientists before them as he or she inherits their studies and any conclusions that superseded it. Unlike myth, which is a means of explaining the natural world through means other than logical criticism, scientific tradition was inherited from Socrates, who proposed critical discussion, according to Popper. For Thomas Kuhn, who presented his thoughts in a paper presented in 1977, a sense of such a critical inheritance of tradition is, historically, what sets apart the best scientists who change their fields is an embracement of tradition.