Sexual desire, without Eros, wants it, the thing in itself; Eros wants the Beloved. The thing is a sensory pleasure; that is, an event occurring within one’s own body. We use a most unfortunate idiom when we say, of a lustful man prowling the streets, at he “wants a woman.” Strictly speaking, a woman is just what he does not want. He wants a pleasure for which a woman happens to be the necessary piece of apparatus. How much he cares about the woman as such may be gauged by his attitude to her five minutes after fruition (one does not keep the carton after one has smoked the cigarettes). Now Eros makes a man really want, not a woman, but one particular woman. In some mysterious but quite indisputable fashion the lover desires the Beloved herself, not the pleasure she can give.
C.S. Lewis, The Four Loves (1960; Harcourt Brace: 1991) 91, 94.