divine essentiality or essentialist theology would influence Richard of St. Victor, Alexander of Hales and St. Bonaventure. By this method, the essence of God is defined by what God is, and also by describing what God is not (negative theology). St. Thomas took the text of Exodus beyond the explanation of essential theology. He bridged the gap of understanding between the being of essence and the being of existence. In Summa Theologica, the way is prepared with the proofs for the existence of God. All that remained was to recognize the God of Exodus as having the nature of "Him Who is the supreme act of being". God is simple, there is no composition in God. In this regard, Aquinas relied on Boethius who in turn followed the path of Platonism, something Aquinas usually avoided. The conclusion was that the meaning of "I Am Who Am" is not an enigma to be answered, but the statement of the essence of God. This is the discovery of Aquinas: the essence of God is not described by negative analogy, but the "essence of God is to exist". This is the basis of "existential theology" and leads to what Gilson calls the first and only existential philosophy. In Latin, this is called "Haec Sublimis Veritas", "the sublime truth". The revealed essence of God is to exist, or in the words of Aquinas, I am the pure Act of Being. This has been described as the key to understanding Thomism. Thomism has been described (as a philosophical movement), as either the emptiest, or the fullest of philosophies. Creation As a Catholic Thomas believed that God is the "maker of heaven and earth, of all that is visible and invisible." Like Aristotle, Thomas posited that life could form from non-living material or plant life: Additionally Thomas considered Empedocles's theory that various mutated species emerged at the dawn of Creation. Thomas reasoned that these species were generated through mutations in animal sperm, and argued that they were not unintended by nature; rather, such species were simply not intended for perpetual existence. That discussion is found in his commentary on Aristotle's Physics: Just war While it would be contradictory to speak of a "just schism", a "just brawling" or a "just sedition", the word "war" permits sub-classification into good and bad kinds. Thomas Aquinas, centuries after Augustine of Hippo, used the authority of Augustine's arguments in an