“My [Houyhnhnm] master … said, a fancy would sometimes take a Yahoo to retire into a corner, to lie down, and howl, and groan, and spurn away all that came near him, although he were young and fat, wanted neither food nor water, nor did the servant imagine what could possibly ail him. And the only remedy they found was, to set him to hard work, after which he would infallibly come to himself. To this I was silent out of partiality to my own kind; yet here I could plainly discover the true seeds of spleen, which only seizes on the lazy, the luxurious, and the rich; who, if they were forced to undergo the same regimen, I would undertake for the cure.”
Jonathan Swift Gulliver’s Travels