Gulliver's Character Development

While reading part IV I focused a lot on Gulliver's character development. In class we had discussed possible instances in the first two parts of the novel where Gulliver's character was possibly developing, and Professor Porter told us that scholars still debate the extent of Gulliver's character development. Throughout the fourth part, I couldn't help but come to the conclusion that Gulliver actually regresses from parts I and II. In the first two parts we see Gulliver learning things, and we sympathize and relate to his character and circumstances. However, in Part IV Gulliver seems to go off the deep end from spending so much time with horses. He becomes alienated from human society, talks to horses for hours when he gets home, and hates his family. It's as if he spent so many years looking for somewhere better to live than in Europe that he became completely detached from human society, and the reader loses faith in him.