[xcv123]

The opponents strategy is an unknown variable not determined by the current board state.

Therefore the best move cannot be determined by the current board state, as it cannot be determined in isolation from the opponents strategy.

[janalsncm]

The optimal strategy can be determined from the current state. This is the principle behind minimax.

In a perfect information zero sum game, we can theoretically draw a complete game tree, each terminal node ending with a win, loss, or draw. With a full understanding of the game tree we can make moves to minimize our opponent’s best move.

[xcv123]

I stand corrected. Thanks for that explanation.