What subsequent philosophy, down to quite modern times, accepted from Parmenides, was not the impossibility of all change, which was too violent a paradox, but the indestructibility of substance. The word substance did not occur in his immediate successors, but the concept is already present in their speculations. A substance was supposed to be the persistent subject of varying predicates. As such it became, and remained for more than two thousand years, one of the fundamental concepts in philosophy, psychology, physics, and theology.p. 52.