What is the title of Tolkien’s 1939 lecture that became a famous essay about fantasy?

Tolkien’s 1939 lecture about fantasy is titled “On Fairy-Stories.”

Tolkien first delivered the work as the Andrew Lang lecture at the University of St Andrews in Scotland on 8 March 1939. It was later revised and published in essay form, becoming one of his most influential statements about fairy stories, imagination, and literary fantasy.

In the essay, Tolkien discusses the functions of fairy stories, including recovery, escape, and consolation. He also argues that fantasy can present a coherent secondary world rather than being merely an escape from reality. His ideas are often connected with his own practice as a writer and world-builder.

The title is sometimes confused with “The Monsters and the Critics,” another important Tolkien lecture and essay. “Leaf by Niggle” is a short story, while “A Secret Vice” concerns invented languages.