As that word 'pure' fell from her lips, I heard the trembling of the plaintive 'u,' the icy limpidity of the 'r,' and the sound aroused nothing in me but the need to hear again its unique resonance, its echo of a drop that trickles out, breaks off, and falls somewhere with a splash. The word 'pure' has never revealed an intelligible meaning to me. I can only use the word to quench an optical thirst for purity in the transparencies that evoke it - in bubbles, in a volume of water, and in the imaginary latitudes entrenched, beyond reach, at the very centre of a dense crystal.
Colette - Ces plaisirs, Le pur et l'impur, 1932