The chess board is the world, the pieces are the phenomena of the universe, the rules of the game are what we call the laws of Nature. The player on the other side is hidden from us. We know that his play is always fair, just and patient. We also know, to our cost, that he never overlooks a mistake, or makes the smallest allowance for ignorance.
-Thomas Huxley
I've traditionally gone with: the board is the space of/for potentially-live hypotheses/arguments/considerations, pieces are facts/observations/common-knowledge-arguments, moves are new arguments, the rules are the rules of epistemology. This lets you bring in other metaphors: ideally your pieces (facts/common-knowledge-arguments) should be overprotected (supported by other facts/common-knowledge-arguments); you should watch out for zwichenzugs (arguments that redeem other arguments that it would otherwise be justified to ignore); tactics/combinations (goo...
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