For the first time, Gulliver finds himself wanting to stay in exile from humanity, but he is not given the choice. He is appalled by the idea of going to live among the Yahoos, and he has so fully adopted the belief system of the Houyhnhnms that he cannot help but see his wife and children as primitive, ugly, beastlike creatures. But at the same time, he realizes that he has been living with the Houyhnhnms on borrowed time, pretending only half-successfully to be as rational as they are. The simplicity of the Houyhnhnms’ world attracts him, but it is not a world in which he is allowed to live. In the end, he is forced to return to the world from which he came—a single world that encompasses all of the flaws and complexities he has encountered in his travels. But even there Gulliver cannot rest easy. Having seen the things he has, the world of Yahoos is contemptible and disgusting to him. Barely able to tolerate the presence of his family, he retreats into a kind of madness, spending his days talking to the horses in his stable as if to recreate the idyll of Houyhnhnmland.
In the first three voyages, it is easy to identify with Gulliver, but in the last voyage he becomes so alienated from humanity that it is difficult to sympathize with him. This shift in our loyalty is accompanied by a shift in the method of satire. Whereas in the first voyages we can look through Gulliver’s eyes—sharing his astonishment at the Lilliputians’ miniature society, his discomfort at being the plaything of the Brobdingnagian giants, and his contempt for the tyrannical intellectualism of the Laputans—here, in the fourth voyage, we are forced to step back and look not with Gulliver, but at him.
Although in some ways the Houyhnhnms are the ideal for which Gulliver strives unsuccessfully among his fellow humans, in another way they are just as much the victims of Swift’s satire as the peoples of the first three voyages. Paragons of virtue and rationality, the horses are also dull, simple, and lifeless. Their language is impoverished, their mating loveless, and their understanding of the complex play of social forces naïve. What is missing in the horses is exactly that which makes human life rich: the complicated interplay of selfishness, altruism, love, hate, and all other emotions. In other words, the Houyhnhnms’ society is perfect for Houyhnhnms, but it is hopeless for humans. Houyhnhnm society is, in stark contrast to the societies of the first three voyages, devoid of all that is human.