One-third, more or less, of all the sorrow . . . [we] must endure is . . .  inherent in the human condition, the price we must pay for being sentient and self-conscious organisms, aspirants to liberation, but subject to the laws of nature and under orders to keep on marching, through irreversible time . . . toward decrepitude and the certainty of death. The remaining two-thirds of all sorrow is homemade and, so far as the universe is concerned, unnecessary.

—Aldous Huxley

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