When reference is made in the discussion to a principle using eq 1, eq 2, etc. A link is provide to the discussion of each principle.
Proposition is a statement that can be asserted as either true or false.
They are called general or arbitrary or variables. A simple statement declares only one thing about one subject. A compound statement contains two or more simple statements. Or it modifies a simple statement. The truth value of compound statements depend on the truth value of the simple statements contained in them.