What ultimately leads Gulliver to reject human interaction upon his return to England?

Gulliver's rejection of human interaction upon his return to England stems from his profound disdain for the societal norms he observes in his native society. Throughout his travels, particularly in his encounter with the Houyhnbns—intelligent and rational horse-like creatures—he comes to admire their logical, harmonious way of life. In stark contrast, he is appalled by the corruption, vice, and vanity he sees in humans, which he perceives as inferior and base. This deep-seated contempt for the flaws of humanity leads to a sense of alienation and disillusionment with human society. Ultimately, he decides to isolate himself to distance from those ignoble qualities that he no longer wishes to be associated with, rejecting the interactions he once sought.