Reason and logic in Metaphysics & Epistemology Posted 3 Oct 2014 · Report post I'm no expert here, but that looks like a definition to me because of what it excludes. It can only be read one way. For example, "Faith" cannot integrate the material of the senses, and is thus excluded from substitution. At the same time "identifies" and "integrates" are isolated differentia that form the definition of reason. That is my understanding anyway.