It is often maintained that friendship between men and women can never approach the high level of friendship between men. How, it is objected, could sensuality not be present in such relationships? if it were not present, would not the least coquettish of women feel herself humiliated? It is contrary to every natural impulse for a man to associate with a woman as freely as is usual in friendship without occasionally being conscious of physical desire, and if he is conscious of it, the whole machinery of the passions is set in motion.

Un Art de Vivre (The Art of Living) (1939) - The Art of Friendship