“The prerequisite of contrapuntal art, more conspicuous in the work of Bach than in that of any other composer, is an ability to conceive a priori of melodic identities which when transposed, inverted, made retrograde, or transformed rhythmically will yet exhibit, in conjunction with the original subject matter, some entirely new but completely harmonious profile.”
Source : "Song: 'So You Want To Write A Fugue'". 1997.
