lthough a powerful literary argument can be made for the revelatory power of sex, many texts present a powerful counterargument, testifying to the power of sexual fantasy and the evidence that sex is a lie.
Sex can raise or lower our perception of a partner, moving us (according to later, retrospective judgment) from illusion to truth, or from truth to illusion. The permutations are complex, if not infinite, because there are several variables, each of which may prove illusory. Sometimes we are deluded about our partners, on whom we project our own fantasies (before, after or during the sexual act); sometimes we delude ourselves with fantasies about ourselves, thinking that we are animals seeking animal partners, when in fact we are looking for gods, or the reverse; sometimes it's all of the above. "Whatever can he see in her?" we ask one another about our friends, and often, as Wordsworth defined the origins of poetry, when emotion is recollected in tranquility, "Whatever did I see in him?" (see, indeed--or, rather, project onto him as a visual image). We all suffer from bovarysme, named after the heroine of Flaubert's novel Madame Bovary, who deluded herself constantly, especially about sexual love. It is easier to find someone to go to bed with than to find someone to wake up with; we need a different sort of morning-after pill, a mental rather than physical retroactive contraceptive.
clipped from: fathom.lib.uchicago.edu 
lthough a powerful literary argument can be made for the revelatory power of sex, many texts present a powerful counterargument, testifying to the power of sexual fantasy and the evidence that sex is a lie.