"The Circular Ruins" is a fantasy short story by Argentine author Jorge Luis Borges. It was first published in Spanish in 1940. An English translation was first published in the UK in 1949. It is included in the collections Fictions and The Garden of Forking Paths.
The story is about a man who creates another man through his dreams. The created man is a mental creation. The original man finds at the end that he is also a mental creation of another author, possibly Borges himself.