"I am taking such pains with these things, not so much out of concern that the pupil might, if they were not explained, thoughtlessly accept and mechanically apply them, as to establish explicitly that these principles are not derived from aesthetics but from practical considerations. If what is known as aesthetics does in fact contain much that is merely practical handling of the material, and if what is known as symmetry is perhaps often not much more than an organization of the material that reveals a sensible regard for its properties, yet I consider it worthwhile to set down these observations. For the conditions of practicality can change, if we take a different view of the material and if the purpose changes. But aesthetics alleges it has discovered eternal laws."

-- Arnold Schoenberg, Theory of Harmony