3 ms·
not really valid as white becomes black.
by kostyk 11y ago
not really valid as white becomes black.
- ColinWright 11y agoDid you actually read right to the end? "But in fact, at the time this game was played there was no specific rule stating that a pawn had to be promoted to a piece of the same colour!
- ubernostrum 11y agoOf course there was also no rule saying that chess functioned on a restrictive rules system and a lot of evidence that it instead functioned on a permissive system. Which would invalidate the "no rule says I can't" argument. (when designing a game's rules, "restrictive" means the approach is "everything is permitted by default, unless explicitly restricted", while "permissive" means "everything is forbidden by default unless explicitly permitted" -- if we assume that chess is a restrictive-rules game, we can similarly mate in one from almost any position by simply inventing new pieces with unusual abilities and declaring that "the rules don't say you can't!")
- mikeash 11y agoIf the rule was simply, "A promoted pawn may be exchanged for any piece," then that would fit within a permissive system, and still qualify as "nothing says you have to promote to the same color."
- Maken 11y agoSo, promoting a pawn in chess is undefined behavior?
- dragonwriter 11y agoNo, its defined (both then and now), its just the spec has had breaking changes from earlier versions.
- lmm 11y agoNo. It was unclear whether you could promote to a piece of the other colour, but a conforming implementation of chess will not make demons fly out of your nose.
- Nano2rad 11y agoCan it be called promotion then, it is like country A promoting its soldier to general of country B. What will happen it is not endgame. Who will move the black knight promoted by white side?