Sex also concentrates the mind wonderfully, and that is why civilised man is so obsessed by it. It enables him to "savour every fraction of an inch," not merely of the act of sexual intercourse, but of living itself. But that, of course, only underlines the basic problem: after coitus, "man becomes sad," because he quickly returns to his unconcentrated and defocused state. In sexual excitement, it is the spirit itself that becomes erect, and becomes capable of penetrating the meaning of life. Normal consciousness is limp and flaccid; its attitude towards reality is defensive. This is what Sartre called contingency, that feeling of being at the mercy of chance.