What is the effect of Gulliver's prolonged stay in the land of the Houyhnbnms?

The effect of Gulliver's prolonged stay in the land of the Houyhnbnms is that he adopts their rational ways, leading him to question his own nature. The Houyhnbnms are depicted as rational, intelligent horses who live in a society governed by reason and devoid of the vices common in human culture. By immersing himself in their way of life, Gulliver begins to reflect critically on human behaviors and the flaws that plague society, such as deceit and corruption. This journey prompts him to reassess his own identity and the values he previously held dear, ultimately creating a profound internal conflict between the rationality he admires in the Houyhnbnms and the irrational tendencies he recognizes in humanity. This transformation illustrates the broader theme of the novel, which critiques human nature and societal constructs.