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.

Capitalism, the Unknown Ideal (ed. Signet Book, 1966)