Whenever the mind of the artist suffers itself to be occupied, during its periods of creation, by any other predominant motive than the desire of beauty, the result is false in art.
Source, in full
"On Some of the Characteristics of Modern Poetry, and on the Lyrical Poems of Alfred Tennyson", in The Englishman's Magazine (August 1831), p. 616; "Extract from a Review of Tennyson's Poems", in Arthur Henry Hallam, Remains in Verse and Prose (London: John Murray, 1862), p. 294. Variant quoted by Kingsley Amis, The Biographer's Moustache (London: Flamingo, 1995), p. 176: "Hallam wrote somewhere that unless a poet writes predominantly to create beauty, the result will be false in art."