Nevertheless, in determining the artistic value of the work, the
question goes not to the ingenuity of the programme or the clearness
with which its suggestions have been carried out, but to the beauty of
the music itself irrespective of the verbal commentary accompanying
it. This rule must be maintained in order to prevent a degradation of
the object of musical expression. The vile, the ugly, the painful are
not fit subjects for music; music renounces, contravenes, negatives
itself when it attempts their delineation.

A classification of Programme music might be made on these lines:

[Sidenote: _Kinds of Programme music._]

I. Descriptive pieces which rest on imitation or suggestion of natural
sounds.

II. Pieces whose contents are purely musical, but the mood of which is
suggested by a poetical title.

III. Pieces in which the influence which determined their form and
development is indicated not only by a title but also by a motto which
is relied upon to mark out a train of thought for the listener which
will bring his fancy into union with that of the composer. The motto
may be verbal or pictorial.

IV. Symphonies or other composite works which have a title to indicate
their general character, supplemented by explanatory superscriptions
for each portion.

[Sidenote: _Imitation of natural sounds._]