Robert Musil

The desire for a double of the other sex that resembles us absolutely while still being other, for a magical creature who is ourself while possessing the advantage, over all our imaginings, of an autonomous existence . . . We find traces of it in even the most banal circumstances of love: in the attraction linked to any change, any disguise, as in the importance of unison and the repetition of the self in other . . . The great, the implacable amorous passions are all linked to the fact that a being imagines he sees his most secret self spying upon him behind the curtain of another's eyes.

Robert Musil, quoted in The Art of Seduction (Robert Greene)