Gulliver resolves that he would rather live out the rest of his life on an uninhabited island than return to live amongst Yahoos. He lands on one he thinks is uninhabited but is soon chased off by savages who shoot arrows at him, scarring his knee. When he next pulls up on shore, he is discovered by the crew of a Portuguese ship captained by Don Pedro de Mendez. They are all baffled by Gulliver’s resolution not to return to live with Yahoos and laugh at his horsey voice and strange clothes. When they insist he board their ship to return to Europe, he is extremely reluctant to and tries to kill himself by jumping into the sea. A crew member captures him before he falls and Gulliver is chained to his cabin. Gulliver is repulsed by the sight of the humans around him.
Adopting the Houyhnhmn perspective has stranded Gulliver between societies—he won’t be accepted by the Houyhnhmns and he can’t himself accept the human society of England. From Don Pedro and his crew’s perspective, Gulliver’s “elevated” Houyhnhmn habits are absurd and laughable.
During the rest of the voyage, Don Pedro acts tenderly towards Gulliver, listening to him and gradually beginning to believe his stories (even though he first seems to suspect Gulliver is lying). He makes Gulliver promise not to kill himself and, when they reach Portugal, takes Gulliver into his own bachelor’s home and gives him a new set of clothes. He helps Gulliver ease slowly back into familiarity with human society. He eventually convinces Gulliver that he should return to his family in England.
Despite Gulliver’s conviction that human beings are immoral and repulsive, Don Pedro acts as tenderly as the master horse did, listening to Gulliver describe what seems at first an unbelievable account of Houyhnhmn culture just as the master horse listened to Gulliver describe the European society he initially thought was a lie.
Gulliver sails back to England where his family, it turns out, has presumed him dead. He refers to his wife as “that odious animal” and faints at her embrace. He tells the reader that, at the time of writing, it has been five years since he’s been back in England and he still can’t stand the sight, smell, or presence of his wife and his children. Upon his return, he immediately buys two horses and dotes on them, never saddling or bridling them and spending as much time with them in the stable as he can. The only human he likes is the groom, because he smells like a horse.
Indeed, Gulliver’s new perspective and worldly knowledge have crippled him in human society. He is alienated from all people, even his own family members, and can no longer see humans as loved ones or fellow companions. His effort to recreate Houyhnhmn society by buying two irrational European horses proves equally futile.