What is the main theme of the story ‘Swimming Lessons’?

In almost an autobiographical mood, Mistry points out the difficulties he faced in Canada; he was unable to swim with the tide and how learning swimming reflect the difficulties he faced as an immigrant.

Once he learns to swim, that would symbolize his overcoming the problems of being an immigrant, he would become one with the Canadians, though, not necessarily their equal. There are sexual overtones to many of the narrator’s dreams, which are handled very realistically as well as ironically- it is but natural for a young man living alone to have voyeuristic dreams.