Aristotle's metaphysics presents a response to the objections posed due to Plato's theory of forms of the Universal as presented in Book VII of the Republic. He faltered in the formulation of the theory of forms believing that ultimate reality is reflected in ideas or eternal forms knowable only through reflection and reason. He places ideas, essence of things outside themselves thus engaging in a self contradiction according to Aristotle. Metaphysics Book Zeta attempts to reconcile this mistake by presenting an argument that being, reality of substances lies in their concrete forms. In order to do so, he probed some of the deepest questions of philosophy, existence and change. Here a link between Aristotle?s categories and Physics is established through the concept of predication at the very beginning of the inquiry into being.
Plato's understanding of being was based on its existential role alone, Aristotle proclaimed that being could also be attributed with predicates like in the form of quality, quantity, in time and so on.
Change too can be expressed in terms of becoming of matter partaking different forms through the privation of 'to be'. So the verb to be indicates both existence and change and is imperative in Arristotle?s philosophy to reconcile 1. Noun and verb. 2. Universal and particular.3. Existence and attribution.
Based on the analysis of the nature of substance in the categories primary substance is the best candidate for being because
1. Its independent existence and dependence of non substance categories in time.
2. In defining some being the definition of its substance must be present.
3. Also we think we know a thing most clearly if we point towards the individual or the primary being.
So the age old question of ?what is being?? becomes ?what is primary being? or substance?...