In the far future, a celebration of the survival of humanity will be held on the third Monday of every May, known as Miracle Monday. As time traveller Kristin Wells discovered when she returned to the past to find out the origins of the holiday, it was originally started to honor the time that Superman triumphed over Satan. Huh.
To celebrate: Rejoice both in the continued existence of man and in the strange world we live in where there was a novel about Superman defeating Satan with the help of a time-traveller.
(Superman: Miracle Monday, Book, 1981)