1. (n.) A doctrine, or scheme of things, which terminates in speculation or contemplation, without a view to practice; hypothesis; speculation.

2. (n.) An exposition of the general or abstract principles of any science; as, the theory of music.

3. (n.) The science, as distinguished from the art; as, the theory and practice of medicine.

4. (n.) The philosophical explanation of phenomena, either physical or moral; as, Lavoisier's theory of combustion; Adam Smith's theory of moral sentiments.

apprehension assumption attitude base basis body of theory climate of opinion common belief community sentiment conceit concept conception conclusion conjecture consensus gentium consideration estimate estimation ethos explanation eye fancy feeling general belief grounds guess guesswork harmonics harmony hunch hypothesis idea image imago impression intellectual object judgment lights melodics memory-trace mental image mental impression mind music music theory musicality musicography musicology mystique notion observation opinion perception perhaps personal judgment point of view popular belief position posture premise presentiment presumption prevailing belief public belief public opinion reaction recept reflection representation rhythmics sentiment sight speculation stance supposal suppose supposition surmise suspicion tentative explanation theoretical structure there thinking thither thitherward thought understanding unified theory view way of thinking yon yonder