Composition with Twelve Tones:
In every composition preceding the method of composing with twelve tones, all the thematic and harmonic material is primarily derived from three sources: the tonality, the basic motive which in turn is a derivative of the tonality, and the rhythm, which is included in the basic motive. A composer's whole thinking was bound to remain in an intelligible manner around the central root. A composition which failed to obey these demands was considered "amateurish;" but a composition which adhered to it rigorously was never called "cerebral." On the contrary, the capacity to obey the principle instinctively was considered a natural condition of a talent.
The time will come when the ability to draw thematic material from a basic set of twelve tones will be an unconditional prerequisite for obtaining admission into the composition class of a conservatory.