Which 1939 lecture by J.R.R. Tolkien discussed fantasy, recovery, escape, and consolation?

J.R.R. Tolkien’s 1939 lecture discussing fantasy, recovery, escape, and consolation was titled On Fairy-Stories.

Tolkien delivered the lecture as the Andrew Lang Lecture at the University of St Andrews in Scotland. He argued that fairy-stories should not be reduced to children’s entertainment and proposed that they could offer serious imaginative and emotional value.

The essay is especially known for its discussion of the “sub-creation” of coherent secondary worlds. Tolkien also described recovery as seeing familiar things afresh, escape as a legitimate response to the limitations of ordinary life, and consolation as the joy associated with a good catastrophe. The expanded essay was later published in print and became a major statement of Tolkien’s theory of fantasy.