“On Fairy-Stories” is an essay by J. R. R. Tolkien which discusses the fairy-story as a literary form. It was initially written (and entitled simply “Fairy Stories”) for presentation by Tolkien as the Andrew Lang lecture at the University of St Andrews, Scotland, on 8 March 1939.

https://en.wikipedia.org/wiki/On_Fairy-Stories

Tis a bit weird that I somehow happened to be reading about this 80 years to the day that it happened, and only a stone’s throw away.