This axiom implies that everything has a specific nature and that everything acts in accordance with its nature. Man posses consciousness, which is the faculty of perceiving that which exists. This is also a corollary of the first axiom. The second branch of Objectivist philosophy is epistemology . The Objectivist epistemology says that reason is the method of man's consciousness.
Reason is the process of forming and using concepts.
A human consciousness forms a concept by observing a number of similar concretes and mentally integrating them into one idea. The measurements of the concrete objects are omitted, and the concept subsumes the qualities that the concretes have in common. Reason also includes logic. Logic is the art of noncontradictory identification. Logic involves using concepts to draw conclusions.