The notion of the temporal infinity was familiar to the Greek mind from remote antiquity in the religious conception of immortality.[clarification needed][1] This idea of the divine as an origin[clarification needed] influenced the first Greek philosophers.[17] The main object of the first efforts to explain the world remained the description of its growth, from a beginning. They believed that the world arose out from a primal unity, and that this substance was the permanent base of all its being. Anaximander claims that the origin is apeiron (the unlimited), a divine and perpetual substance less definite than the common elements.