Definition of: rationalism

(rash′ən·əl·iz′əm) noun
1. The formation of opinions by relying upon reason alone, independently of authority or of revelation: opposed to supernaturalism.
2. Philos. a The theory of a priori ideas, that truth and knowledge are attainable through reason rather than through experience: opposed to empiricism. b The theory that reason itself is a source of knowledge independent of sense perception: opposed to sensationalism.
—ra′tion·al·ist noun
—ra′tion·al·is′tic or ·ti·cal adjective
—ra′tion·al·is′ti·cal·ly adverb