Also does not rely on authority like religion. Aesthetics - studies the nature of art, beauty, and related questions. Logic - studies reasoning, esp. Closely related to, but not the same as, epistemology. More on logic later.
Logic is very important to philosophy, due to the central role of argumentation in philosophy.
1. Statements 2. A proposition requires both a subject and a predicate. Intermediary steps - other statements showing how the premises lead to the conclusion. Validity - An argument is valid iff it is logically impossible that all the premises be true and the conclusion be false. Soundness - an argument is sound iff it is both valid and has all true premises.