Which 1939 lecture by J.R.R. Tolkien discusses the nature and purpose of fantasy stories?

J.R.R. Tolkien’s 1939 lecture about the nature and purpose of fantasy stories was titled On Fairy-Stories. He delivered it as the Andrew Lang lecture at the University of St Andrews in Scotland on 8 March 1939.

The essay was later revised and published in 1947. In it, Tolkien considers what a fairy-story is, who it is for, and what kinds of value it can offer. He discusses concepts including recovery, escape, and consolation, while also defending fantasy against the idea that it is merely childish or detached from serious life.

Tolkien’s argument is closely connected with his own work as a philologist and storyteller. He emphasizes the importance of the imagined secondary world, where events can be internally consistent even though the world is not our primary reality. His discussion of “sub-creation” became especially influential in later fantasy criticism.

On Fairy-Stories is an essay about literary theory, not a fictional tale. It is often read alongside Tolkien’s fiction because it explains several principles visible in The Hobbit and The Lord of the Rings, but it does not function as a plot summary of either book.