Math Story: What Is a Perfect Information Game

“Perfect... what?”

When a difficult word came up, Arin tilted her head.

“I'll explain it as simply as I can. When Arin plays chess, how can she win? What's the best move right now? That's what she always thinks about, right?”

“Yeah! That's what I always think about.”

“That's the normal way to play a game. But mathematicians go one step further and think about the essence.”

I brought a whiteboard and laid it on the living room floor. Then I scribbled on it.

……………………………………

“Is this a winnable game?”

“Does a guaranteed winning strategy exist?”

“Can the game itself be expressed mathematically?”...