"It is perhaps scarcely an exaggeration to claim that, in this opera, the entire 'natural' musical order of things is inverted; 'inverted' being the operative (and in this case appositely loaded) word, since the result of inverting a perfect fourth is a perfect fifth, and what is the musical meaning of 'Quint' but a fifth? I am aware that this is in effect asking the reader to accept that the entire musical structure of The Turn of the Screw was motivated by a pun; and while I feel that Britten must have been aware of the musical implications of Quint's name, I think it likely that they unconsciously, rather than consciously, influenced his choice of vocabulary. Whatever the facts of this matter, we should not be chary of recognising Britten's achievement (a) in creating a sense of all-pervasive evil through the very musical formulas normally and naturally (but there is nothing 'normal' or 'natural' about The Turn of the Screw) associated with all-pervasive good, and (b) in avoiding totally the cliché of the augmented fourth/diminished fifth, the conventional, traditional diabolus in musica."
-- Christopher Palmer, "An Inversion of the Natural Order" (liner notes to Britten's original 1954 recording of the opera on Decca/London Records)
-- Christopher Palmer, "An Inversion of the Natural Order" (liner notes to Britten's original 1954 recording of the opera on Decca/London Records)