In the game of chess, your opponent's pieces and moves are all

visible. We say that chess is a game with complete information. In games such as

bridge or poker, however, you do not know how the cards have been dealt. Does

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Section $2\mathrm{.}9$ Problems

this make it impossible to define an algorithm for playing good bridge or poker?

Would such an algorithm necessarily be probabilistic?

What about backgammon? Here you can see your opponent's pieces and moves,

but you cannot predict how the dice will fall on future throws. Does this alter the

situation?