"That sulphuric acid dissolves certain metals is beyond question; but something superior, once placed in question, is no longer superior, for it must do something special to respond. So it is here: if a tone, for example C, is followed by another tone, for example G, it raises a doubt as to whether C is a tonic (as I say), and now that C must first prove itself by, for example, bringing C back and possibly allowing other characteristic pitches to follow: for example, a, f, d, b, c. But such a series has many possible meanings, and for this reason the tonic must make great efforts to prevail, just as a revolutionary party after attaining power must make powerless all who at any time had got in its way."

— Arnold Schoenberg, The Musical Idea trans. Patricia Carpenter and Severine Neff