Aldous Huxley here likens music to the Trinity due to its capacity to say more than one thing at the same time, and then to combine those into a single thing.

Music can say four or five different things at the same time, and can say them in such a way that the different things will combine into one thing. The nearest approach to a demonstration of the doctrine of the Trinity is a fugue or a good piece of counterpoint.

Source: Aldous Huxley, On Art and Artists (London: Chatto and Windus, 1960), p. 7

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