what is the theme of a voyage to brobdingnag?

Otherness plays a large part in Gulliver's Travels. Throughout his journeys Gulliver never quite fits in, regardless of how long he stays. Partly this is a matter of size. In Lilliput, he is the only giant. In Brobdingnag, everyone else is giant and he is small. Although this size is the opposite of Gulliver's experience in Lilliput, the sense of isolation and "otherness" is similar.