The two pre-Socratic philosophers with their surviving works have both proven to show a great argument concerning the creation; or rather the existence of the universe and what lies in it, as well as some explanations on their belief of the primary substance. However, the most interesting philosophy which they both agree and disagree on in two very different ways in the concept of change in the universe and how it occurs, or better yet if it actually occurs.
Heraclitus has been explained to be an obscure philosopher and whose works have shown to be open to different interpretations. In his work he affirms both change and becoming by using his famous quote, “One may never step in the same river twice,” which in logical thought is written in simple terms for the common people to understand. The two concepts, change and becoming, are thought in terms of life and death: what is overcomes that which is not and vice-versa, and that a quality is more or less conquered by its opposite and causing both to be in constant war. His views on the universe were that of eternity by his belief of the universe being constantly existent; it was never created and cannot be destroyed. On his views of opposites Heraclitus believed that nature is made up mainly of two movements which he explained to be: the upward path and the downward path. The downward path, being the process of life, is like when fire transforms into air, then water and finally earth. The upward path happens in the opposite way, meaning earth changes to water, then air, then fire. Withal, Heraclitus held his belief that the two paths are in fact part of the same process and so they are ultimately the same thing. Like the universe, he believed that it has also existed eternally and cannot be subject to change.
He thought that the primary substance was fire and that in actuality fire was a living force and the guiding force of the