“At first the child is amused by his anus and feces, and gaily inserts his finger into the orifice, smelling it, smearing feces on the walls, playing games of touching objects with his anus, and the like. This is a universal form of play that does the serious work of all play: it reflects the discovery and exercise of natural bodily functions; it masters an area of strangeness; it establishes power and control over the deterministic laws of the natural world; and it does all this with symbols and fancy. With anal play the child is already becoming a philosopher of the human condition. But like all philosophers he is still bound by it, and his main task in life becomes the denial of what the anus represents: that in fact, he is nothing but body so far as nature is concerned. Nature’s values are bodily values, human values are mental values, and though they take the loftiest flights they are built upon excrement, impossible without it, always brought back to it. As Montaigne put it, on the highest throne in the world man sits on his arse. Usually this epigram makes people laugh because it seems to reclaim the world from artificial pride and snobbery and to bring things back to egalitarian values. But if we push the observation even further and say men sit not only on their arse, but over a warm and fuming pile of their own excrement—the joke is no longer funny. The tragedy of man’s dualism, his ludicrous situation, becomes too real. The anus and its incomprehensible, repulsive product represents not only physical determinism and boundness, but the fate as well of all that is physical: decay and death.”

The Recasting of Some Basic Psychoanalytic Ideas
The Denial of Death (1973)