"Truth is the product of the recognition (i.e., identification) of the facts of reality. Man identifies and integrated the facts of reality by means of concepts. He retains concepts in his mind by means of definitions - and the truth and falsehood of the definitions of the concepts he uses to assert them, which rests on the truth or falsehood of his designations of essential characteristics" - Ayn Rand, Introduction to Objectivist Epistemology