Aquinas: Essence And Existence

In order to understand Aquinas’ metaphysics, one must understand the difference between essence and existence. According to Aquinas, there are two senses of ‘being’: one sense is that “those things [are called beings] that are sorted into the ten categories (of Aristotle); in the other sense [calling something a being] signifies the truth of propositions” (Aquinas, I). Then, Aquinas goes on to say that essence is derived from a being in the first sense. Because a being can be divided into ten categories, essence according to Aquinas must be common to all substances of different genera and species. Moreover, essence can be found in its truest and most perfect form in the simplest of substances, which is God.
However, God and other simple substances …show more content…
In On Being and Essence, Aquinas discusses the essence of composite substances. He claims that the essence in composite substance “signifies what is composed of matter and form” (Aquinas, II). In other words, essence is a purposeful combination of form and matter that is essential to the substance that contains essence. Essence is also a universal characteristic among beings, according to the philosopher (Aquinas, II). After establishing that essence is found in composite substances, Aquinas points out that there are three types of composite substance. Composite substances can be classified by genus, by species, and by difference. Not only does he state that essence is found in all these types of composite substances but also that essence is real through its being in the intellect. St. Thomas in this sense agrees with the Averroists and states that “the intellect is what makes universality in things,” (Aquinas, III). This intellect is put into beings through the First Cause, which is God (Aquinas, III). Since all beings which have a soul have