What happens in Part IV of Gulliver's Travels?
After a mutiny on his ship, Gulliver finds himself washed ashore on an unfamiliar coast. He quickly encounters a group of filthy, brutish creatures—naked, hairy, and prone to violent, irrational behavior—which he later learns are called Yahoos. Repulsed by them, he runs away, only to come across two horses that move with a composed, deliberate grace that feels almost ceremonial. The horses scrutinize him closely, communicating in a soft, whinnying language. Gulliver follows them to a well-organized settlement where he is welcomed into the home of a grey horse—the master Houyhnhnm—and his family. In the following days, Gulliver and the grey horse begin the slow process of learning each other's language. When Gulliver finally manages to communicate in basic Houyhnhnm, he tries to convey that he is a rational being, distinct from the Yahoos. The master Houyhnhnm doubts him: Gulliver’s unclothed body bears an unsettling resemblance to that of a Yahoo. The section concludes with Gulliver's horrifying realization that the Yahoos are, in every physical aspect, human beings.
Analysis
Swift executes a sharp satirical twist here: the rational creature is a horse, while the beast is a man. This crafty move creates a sense of deliberate estrangement—Gulliver arrives, as always, as an empirical observer documenting this new world, but Swift cleverly turns this method on its head. The detailed, Defoe-like inventory that Gulliver uses to describe the Yahoos (their posture, their odor, their social squabbles) is exactly what he will soon realize applies to his own kind. The tonal shift is striking: the prose remains calm, almost clinical, until the moment of recognition, where it suddenly shifts into barely contained horror.
The Houyhnhnms are depicted through what’s not there—their virtue is shown not through actions but by the absence of the vices Gulliver has been detailing over three previous journeys. Their language, which is said to resemble High Dutch but feels more elegant, highlights Swift's mockery of European claims to civilized conversation.
The theme of clothing plays a crucial role. Gulliver keeps his clothes on for as long as he can; when the master Houyhnhnm finally sees him naked, the similarity to a Yahoo becomes unmistakable. Here, clothes are not just a social norm but the last fragile barrier between Gulliver's self-image and Swift's critique of humanity. The sequence of chapters also sets up the epistemological trap Swift is laying: the more fluent Gulliver gets in Houyhnhnm, the harder it becomes for him to deceive himself about what he truly is.
Key quotes from Part IV
“I never beheld in all my Travels so disagreeable an Animal, nor one against which I naturally conceived so strong an Antipathy.”
Gulliver's first impression of the Yahoos, delivered in the measured tone of a naturalist — before he understands he is describing humankind.
“The grey Horse came to the Door, and made me a Sign to follow him into the third Room, where I saw a very comely Mare, together with a Colt and Foal, sitting on their Haunches upon Mats of Straw, not unartfully made.”
Gulliver enters the Houyhnhnm household, and Swift's deadpan domesticity — the family scene rendered in perfectly ordinary syntax — quietly dismantles the reader's assumptions about which species is civilised.
“My Horror and Astonishment are not to be described, when I observed, in this abominable Animal, a perfect human Figure.”
The pivotal moment of recognition in which Gulliver confronts a Yahoo directly and is forced to acknowledge the physical identity between the creature and himself.