What does Gulliver ultimately decide to do with his life after his travels?

Gulliver's ultimate decision to isolate himself represents his profound disillusionment with humanity after witnessing various societies during his travels. Through his experiences, he becomes increasingly critical of human nature and societal flaws, leading him to retreat from the world instead of engaging with it. This isolation reflects his despair and the belief that society is fundamentally corrupt and disappointing.

In contrast, the other options involve active engagement with society or a desire to improve it, which starkly contrasts Gulliver's choice to withdraw. He does not seek to campaign for reform, partake in community service, or share his experiences publicly, as he sees little value in humanity. His decision to live in solitude underscores the significant change in his perspective and the overall theme of the story regarding the complexities of human nature and society.