It is the Zermelo's theorem from game theory, which says that a finite 2 person game always has a solution (draw or a winning strategy for black or white).

https://en.m.wikipedia.org/wiki/Zermelo%27s_theorem_(game_theory)

It is the Zermelo's theorem from game theory, which says that a finite 2 person game always has a solution (draw or a winning strategy for black or white).

Zermelo's theorem (game theory)