Just as man's physical existence was liberated when he grasped that 'nature, to be commanded, must be obeyed', so his consciousness will be liberated when grasps that nature, to be apprehended, must be obeyed - that the rules of cognition must be derived from the nature of existence and the nature, the identity, of his cognitive faculty.
Ayn Rand (1988). “The Ayn Rand Lexicon: Objectivism from A to Z”, p.106, Penguin