Since knowledge, thinking, and rational action are properties of the individual, since the choice to exercise his rational faculty or not depends on the individual, man’s survival requires that those who think be free of the interference of those who don’t. Since men are neither omniscient nor infallible, they must be free to agree or disagree, to cooperate or to pursue their own independent course, each according to his own rational judgment. Freedom is the fundamental requirement of man’s mind.A rational mind does not work under compulsion; it does not subordinate its grasp of reality to anyone’s orders, directives, or controls; it does not sacrifice its knowledge, its view of the truth, to anyone’s opinions, threats, wishes, plans, or “welfare.” Such a mind may be hampered by others, it may be silenced, proscribed, imprisoned, or destroyed; it cannot be forced; a gun is not an argument. (An example and symbol of this attitude is Galileo.)It is from the work and the inviolate integrity of such minds—from the intransigent innovators—that all of mankind’s knowledge and achievements have come. (See The Fountainhead.) It is to such minds that mankind owes its survival. (See Atlas Shrugged.)