The general theme of Gulliver's Travels is the inherently amusing nature of human tradition and custom, and the relative nature of morality and society based on historical precedent. Like so many of Jonathan Swift's works, Gulliver's Travels is mostly a satire of British royalty and Imperialism. Swift shows various facets of British life through his fantastic islands, such as the overt political symbolism in Lilliput and the pursuit of knowledge for no greater purpose in the flying island of Laputa. Gulliver acts as both the everyman, representing the reader, and as a person whose ideals and morals are changed by his experiences. One of the works that Swift intentionally satirized was the then-new novel Robinson Crusoe, in which a British man is marooned and becomes self-sufficient and wealthy; Gulliver, in contrast, is constantly captured and held captive by the people he meets, and has no ability to alter his own fate or the circumstances of other nations.