But he heard high up in the air a piper piping away, and never was piping so sad, and never was piping so gay

But he heard high up in the air a piper piping away, and never was piping so sad, and never was piping so gay

The line "But he heard high up in the air a piper piping away, and never was piping so sad, and never was piping so gay" from William Butler Yeats' poem "The Hosting of the Sidhe" captures the essence of duality and contradiction that is often present in Yeats' work. The image of a piper playing a tune that is both sad and gay simultaneously evokes a sense of complexity and depth that is characteristic of Yeats' poetry.