The Forty-Eight Preludes and Fugues of John Sebastian Bach Analysed for the Use of Students #270422

Fugue. — A composition developed upon a certain Subject or theme, which is announced at first in one part only. This theme is imitated according to certain principles by the other parts composing the piece, which, as they follow upon or fly after the theme, give the distinctive title of Fugue (latin, fuga) to this class of composition. Subject — The theme upon which the composition is written. This theme should be (1) Of a moderate length, so as to be retained without effort in the memory; (2) well defined in character, so as to be easily recognised at each appearance; (3) definite in tonality, so that there shall be no possibility of ambiguity as to its key. The Subject Of a Fugue may be proposed in any part whatever. Answer — This is not a new theme, but a transposition of the Subject a fifth above (or a fourth below) by a different voice from that which announced the Subject.