Empedocles, like the Ionian philosophers and the atomists, continued the tradition of tragic thought which tried to find the basis of the relationship of the One and the Many. Each of the various philosophers, following Parmenides, derived from the Eleatics, the conviction that an existence could not pass into non-existence, and vice versa. Yet, each one had his peculiar way of describing this relation of Divine and mortal thought and thus of the relation of the One and the Many. In order to account for change in the world, in accordance with the ontological requirements of the Eleatics, they viewed changes as the result of mixture and separation of unalterable fundamental realities. Empedocles held that the four elements (Water, Air, Earth, and Fire) were those unchangeable fundamental realities, which were themselves transfigured into successive worlds by the powers of Love and Strife (Heraclitus had explicated the Logos or the "unity of opposites").