- Part 4 of Gulliver's Travels describes Gulliver's voyage to the land of the Houyhnhnms, a race of intelligent, noble horses who are the rulers. - The Houyhnhnms live alongside a filthy, savage race called the Yahoos who resemble humans. - By the end of his journey, Gulliver has come to despise humans as much as the Yahoos, seeing humanity's flaws, and cannot bear to be around people when he returns to England.