 Be that as it may, since progress is a historical (history-laden) concept, so is rationality on Laudan’s conception, as it was on Lakatos’s. The temporality of his account led Laudan to introduce an important distinction between acceptance of a theory and pursuit that would explain how rational transitions to a new research tradition are possible. Scientists should accept the theory that, pro tem, has the greatest overall problem-solving success, but pursue the tradition that now enjoys a higher rate of success. Nearly everyone today accepts a distinction of this sort, although not necessarily Laudan’s criteria of success.