glee, in your first puzzle (the en passant one), was the previous move by White g5-h6 capturing a rook? That’s the only possible precursor I can see.
Interesting, but I think that would have been more confusing than helpful when I was learning chess. I needed to learn the en passant rule. And it would have been nice to see situations where en passant is useful. But the crux of that problem is in proving that the previous move must have been an en passant capture, which isn’t quite the same thing.
Link.
Took a couple minutes, but I got it.
Link.
Got it. Easier, but still interesting.
I took the spoiler tags out. When I put spoilers in a quote, it seems like the content isn’t hidden anymore. Is it just me who sees the spoiler, when I quote it in my own post, or does everyone see spoilers inside quotes?
I hadn’t considered White’s previous move, but there must be a lot e.g.:
- Re8 x Bf8
- Kg4 x Qh5
- pe4 x Nf5
It’s not a legal position (e.g. how did the White pawn get to a6 when no Black pieces have been captured?), so why should the rules of chess apply?
Also from an aesthetic viewpoint, most of the pieces are unnecessary…
Yeah, that’s the main complaint I have about that puzzle is that it’s not a legal board position. The same puzzle could have been made, I assume, without that mess. I personally find it an interesting logic puzzle: knowing that white’s next move leads to checkmate, under what conditions would this be possible? And there is only one possible answer. Perhaps the question should be phrased more finely, like the above. But knowing that 1) White mates on the next move, there’s only one way in which can possibly be achieved. I suppose it “assumes facts not in evidence,” but I’d counter that knowing white mates on the next move provides a way to deduce that fact. It is solvable with all the information given.
The puzzle rests on proving that the previous move by black was with the pawn. Any of the squares the black king could have moved from are under attack. You need to consider white’s previous move, too. Is it possible that white put the black king in check, then black moved his king out of check to h7?
Fortunately for the puzzle, I don’t think that’s possible. But you do need to consider white’s previous move in order to prove it.
Ah, I see what you mean.
I made sure that the Black King couldn’t have moved out of check on the previous move by having each square the king could have come from either occupied by a white piece or attacked by two White pieces (with no possibility of discovered check.)
I have a pedestrian understanding of chess, so I figured it was en passe - but I couldn’t figure out where or how it had been used. I did see that the black pawn deep into white territory would have had to have taken a very aggressive dive during play, which seemed really unlikely.
Unlikely is fine, in a puzzle. You’re allowed to assume that the two players are colluding to reach that position. It’s just impossible that’s considered unfair.
I’d have a hard time finding it, but my favorite chess puzzle involves White underpromoting…
to a black piece. Which isn’t actually legal, but you’ll have a heck of a time finding a copy of the rules comprehensive enough to say so.
I think it might have been in Games Magazine, back in the day.
Looking around, I’m finding other puzzles with the same trick, but the one I remember was more elegant: It had White otherwise at such a disadvantage that the mate-in-one was the only mate possible.
Qg9#
I looked for a discovered check, too, and didn’t find one. There are a lot of possibilities to consider when looking at a chess board and trying to work your way backwards.
Chronos, my understanding was that 50 or so years ago, the official FIDE rules of chess did not prevent promotion to a piece of the opposite colour. Soon after these examples arose, the rules were changed.
Wait, now…what is all this talk about pissants?
mmm