Where Is The White King? | Retrograde Chess Puzzle - Smullyan, 1981

[@roppis9258]

Definitely didn't see it at first but when you mentioned it having to be a double discovered check I realised only one move could do that. For me personally I would prefer a bit more concise explanations, although I think it's good that you also make it so even a beginner could understand what's happening. But each to their own, I like these retrograde puzzles either way

[@ChessforCharity]

Thanks, Roppis! I appreciate the feedback! Thanks for watching!

[@ConcaveDave]

Did you mean only one move in that position or one move at all? Because I’m nearly sure double check is a thing that happens outside of en passant

[@roppis9258]

@@ConcaveDave Yeah I mean in that position specifically. Of course you could get double check in many other ways too in other positions

[@Jivvi]

@@ConcaveDave Double discovered check is not the same as double check. Double discovered check means _both_ checks are discovered, which is only possible when two squares are vacated at the same time.

[@mytherrus2068]

Honestly I really liked the longer explanation, and I feel like shortening it would make it far less accessible to newer players.

[@DrZaius3141]

The weirdest retrograde puzzle I've ever seen was a "draw in 1" puzzle where you'd essentially have to prove that the 50-move-rule applied to it. I remember being impressed but far out of my depth, I can't for the life of me find the puzzle again yet I'd love to have it explained to me.^^

[@ChessforCharity]

That sounds like a lot of fun! I would love to find that one and do a video about it. I will start looking. Thank you for the suggestion! :)

[@Jivvi]

So you had to work out the previous 49 moves? Or at least prove that there couldn't have been any captures or pawn moves.

[@juhak27]

I remember seeing a "mate in 2" puzzle where the correct first move is en passant. It requires a retrograde analysis showing that black's previous move must have been the pawn move allowing the en passant. It was a complex position with a lot of red herrings and no hint that retrograde analysis is required. So basically impossible to solve. And I have no idea where I saw it.

[@Lucashallal]

@@juhak27 search up hardest mate in 2 puzzles and this shows up in a stack exchange post iirc

[@not_vinkami]

I really didn't think that en passant can generate 2 discovers at once Great video and great puzzle!

[@ChessforCharity]

I know what you mean! That caught me by surprise as well when I first saw it. Thanks for watching!

[@undergroundmonorail]

I was nowhere close to solving the puzzle but I did say out loud "is this en pessant somehow" immediately before you said "you have to know this weird rule..."

[@ChessforCharity]

Haha, nice! You have some good instincts! ⭐️

[@hiimemily]

When in doubt, en passant. That's my philosophy. Small wonder that my Elo is still in the 800s...

[@AhsanKhan-xj7mu]

This was very interesting. I haven't seen these types of puzzles anywhere else on KZbin but they're really exciting. Provides a new perspective on the vastness and depth of chess. Thanks for sharing this concept of retrograde puzzles. Really enjoyed the video

[@Michaelonyoutub]

I realized there needed to be two discover checks at the same time, but I had no idea how to do that outside of some potential shenanigans with castling since I could think of nothing else that moves/removes 2 pieces on two separate squares at once besides castling but castling was not the solution in this position since it wasn't near the edge of the board. I had completely forgotten about en passant but as soon as you mentioned it the answer was obvious. I never thought about how en passant can open up two spaces simultaneously like that and how it is mostly unique in that way. Very cool puzzle.

[@ChessforCharity]

I am glad you thought about it so much. It is a fun puzzle. Thank you for watching! 😃

[@steveford1704]

Ingenious puzzle!

[@abj136]

I loved Smullyan’s books. Chess Mysteries of Sherlock Holmes and the Arabian Knights book. All these sorts of puzzles plus some light story telling that as a kid I enjoyed.

[@ChessforCharity]

I love them! I just recently discovered them and they are so cool! I want to spread his work because of how amazing it is! Thank you for watching!

[@Coyotek4]

@@ChessforCharity In addition to his chess books, I also got "What is the Name of This Book", "The Lady or the Tiger", "Alice in Puzzleland", and "Puzzles of Scheherazade". All of these are gems!

[@ChessforCharity]

@@Coyotek4 That is right! I will have to look into those. I am really loving all of his work! Thanks for sharing!

[@AgainstMyBetterJudgement]

I have to admit, I didn't respect this enough to give it a fair shot, but it turns out this channel is very legit. So many times these sorts of puzzle videos have some dumb gimmick where the rules are not clearly and/or properly stated. I thought about en passant briefly but I robbed myself of the opportunity to solve it by dismissing the puzzle outright.

[@ChessforCharity]

I appreciate you giving me the chance. Thank you for watching and providing your feedback. :)

[@heartofthesea572]

holy hell

[@ChessforCharity]

Haha, yep, that is a crazy puzzle! Thank you for watching!

[@shitz8045]

man i was looking for this comment

[@judithcabanero]

holy oxymoron

[@francescof3267]

Really really interesting puzzle !

[@ChessforCharity]

Glad you think so. Thank you for watching!

[@ioannisleventis30]

Great puzzle! In fact Smullyan composed it in 1957. A mirrored version with the King on the board and the goal to find the last move was constructed earlier by B. Pavlovic (Sahovski Vjesnik 1950).

[@ChessforCharity]

That is great to know! Thank you!

[@emmettdja]

I didn't see it all the way through but after a few seconds I decided c3. Turns out I was right! Didn't expect en passant though.

[@ChessforCharity]

Nice work! You guessed right! 🙂

[@parxjohnson2483]

Saw it all the way down to the en passant but didn’t notice the board orientation and thought the pawns were going the other way :/

[@ChessforCharity]

That is great that you saw it so well. Thanks for watching!

[@davidpodnecky2482]

This is beautiful

[@ChessforCharity]

Thank you! 😀

[@_wetmath_]

dang bro that's insane

[@ChessforCharity]

Glad you think so! Thanks for watching!

[@michaelhannappel1999]

Ok this is mind bending

[@ChessforCharity]

That is how I felt! Check out my other retrograde puzzles for other mind boggling ones!

[@alinevennemann1904]

If the white king accidently got knocked over, the king could easily have knocked over a small black stone as well. So, a white king on a3 would be legal as long as we put a black awn on c3. If this shall not count, the puzzle must explicitly state that the white king is the only stone missig.

[@ChessforCharity]

I see what you are saying, but the only way to set the position up legally is to have it on c3. The other information is a necessity through pure deduction. I think it is super cool. Thank you for watching! 🙂

[@grantdillon3420]

My problem was that the puzzle never said that I could add other pieces. I thought this was just a puzzle where the only piece that we were placing was a king in that we weren't allowed to add other pieces to the puzzle

[@ChessforCharity]

I see what you mean. You don’t have to add any pieces in the final position (except for the king), so it is more about understanding the path to get to the final goal. It is a fun challenge. Thank you for watching!

[@Luca-pd6bq]

Thats exactly what he did though (only placing the King). The rest was the explanation of why the King can't be on a3, because that position could not be reached.

[@khangle6872]

The answer was "the king must be on c3". Period That is only the white king added The pawns are just there for explaination, not in the final answer

[@dorukayhanwastaken]

Holy hell!

[@ChessforCharity]

Haha, that is how I felt when I saw this puzzle for the first time! Thanks for watching!

[@judithcabanero]

Is a oxymoron? Is an great one

[@Tyler-bp4md]

veeery nice puzzle

[@ChessforCharity]

Thank you for watching!

[@chainjail4834]

Discovered check means the white auto win or the black can still move their king?

[@ChessforCharity]

That is a good question. Once there is a discovered check, it means that black has to move their king. If they don't have any way of moving their king, blocking the check, or capturing the piece that gave the check, then it would be checkmate and white would win. Thank you for watching! 🙂

[@satishbikki07]

Amazing!!!

[@ChessforCharity]

Thank you!

[@FustinJields]

C3?

[@ChessforCharity]

Nice work! ⭐️

[@balkeesshran4819]

ka7 is answer, board file and rank misplaced when the game starts, white last move was pxa4=B+

[@ChessforCharity]

I am not sure I understand that. Would you be able to explain how the answer I presented is incorrect? Thank you for watching!

[@dannyluo2077]

A pawn is promoted to another piece only when it reaches the enemy’s back rank.

[@kasugaryuichi9767]

This was in Chessmaster! I remember the position.

[@ChessforCharity]

Nice! That is cool! Thank you for watching!

[@hadz8671]

But did the pawn ever get to c4 to block the check? Didn't it get captured as it passed c3?

[@ChessforCharity]

White’s move to block the check was c4. It was on that square when it was black’s move in order to capture it E.P. Thanks for watching!

[@Holital]

Ohhh you have to capture the pawn to get rid of it that's so cute

[@ChessforCharity]

I felt the same way! Thank you for watching!

[@specularspaghet4449]

how was the first thing i thought Kc3 wtf how

[@ChessforCharity]

Haha, that means you are awesome! Nice work!

[@crowreligion]

Finding 62 squares the king is definitely not in was very easy, so I randomly picked between a3 and c3 and i guessed right

[@IamJacksColon4]

but you didnt have the pawn on the board, you never said we could put another black piece on the board. good puzzle however

[@ChessforCharity]

That is true, but that is part of the puzzle. Part of the detective work is realizing that there must have been a pawn in order for the position to be possible. It is super fun. Thanks for watching! 🙂

[@khangle6872]

The final solution require no putting of any black pieces Remember, the question was "where was the white king" The whole en passant thingy is just logic to explain why it is legal, not the answer. And the answer in fact only require one piece - the white king

[@Extrememic]

My question is why is the rook there? Brilliant puzzle, but the position doesn't make sense

[@ChessforCharity]

That is part of the puzzle. It is a way to show that you can get 2 checks with one move. Isn’t that awesome!?

[@petersiegfriedkrug]

I´ve solved this then I saw the picture in seconds. But I am a study composer. And therefore it is much, much easier to solve problems like this.

[@ChessforCharity]

That's great! Thanks for watching!

[@Astrobay13]

I somewhat wish you had given a moment to think about the puzzle at the start of the video instead of immediately explaining the answer, but seeing that the real puzzle only starts after you find out where the king must've been last move, it does kinda make sense that you "rushed" to that part ^^

[@ChessforCharity]

Thanks for the feedback! I think you are right. I was a bit excited and this was one of my first retrograde puzzles. Thank you for watching! 🙂

[@eel9]

Solved it before watching! Took a few minutes ;)

[@ChessforCharity]

Nice work! ⭐️Thank you for watching!

[@ikbenwelthuis]

I don't get why the King can't go to a2 after the en passant Aren't there two legal squares?

[@ChessforCharity]

How would that sequence play out in terms of the pawn? The king is capturing the pawn and ending up on c3. How would that work with a2? That is a great question!

[@Felixr2]

The key to this, is that there is no pawn on c3 in the puzzle. The only way for this position to exist, without a pawn on c3, is if the king captured the c3 pawn after the en passant. Which means that the king must now be on c3.

[@judithcabanero]

It's a retrograde analysis puzzle.

[@dannyluo2077]

If white’s King were on a2, both kings would be in check. That isn’t allowed.

[@MisterBrick42]

I got C3 but from a much more simple idea. White King at C2 and Black King at E1. Black moves king to D1 to check and white moves up for the position shown. I get in this scenario black wouldn’t do that when they have a room but hey I ended up being right

[@ChessforCharity]

Haha, nice work! Thanks for sharing your thought process!

[@Luca-pd6bq]

But that is illegal. What you said was that Black checked white with their King. But that move is illeagal. Just as much as the White King moving to c3, since he would still be in check.

[@thealphabetsong4585]

My mind is blown

[@ChessforCharity]

I am glad you feel that way! I have that feeling every time I look at that problem! 🙂

[@ytmndman]

I figured it out after a few minutes

[@ChessforCharity]

Great work! It is a fun one that takes time. ⭐

[@gachastar8170]

Amazing, I’m not even sure why I said Kc3 too haha

[@ChessforCharity]

Haha, you have great retrograde instincts. :) Thanks for watching!

[@Jarrod0067]

2:21 en passant Edit: called it

[@ChessforCharity]

Haha, nice work! ⭐️

[@ziwuri]

If you're doing these short puzzle videos, you should say whose move it is within the first 10 seconds of the video.

[@ChessforCharity]

Thanks for the feedback. I will certainly do my best to be clearer in the future.

[@Pattonator14]

In this puzzle he doesn't need to though and I think it's actually a great way to have the puzzle start as the approach that you use to figure out who's move it is is the same approach that solves the rest

[@ziwuri]

@@Pattonator14 That's a fair point, that would bring another dimension to the puzzle, but I was honestly confused at first.

[@igorszerszunowicz8049]

But does the white king have to take ? Can't he just go on a3 ?

[@SamMcinturff]

The puzzle is where to place the white king. The king can only be on c3 in the final position, because if it went to a3, because there would be another pawn present in the starting position.

[@ChessforCharity]

You are right that the king does not have to take, but the goal of the puzzle is to find out where to place the king to make this legal. It is a different type of puzzle. Thanks for watching!

[@judithcabanero]

It's a retrograde analysis puzzle.

[@ar1steia486]

I see that r/anarchychess has been spreading the lord's word

[@ChessforCharity]

Haha, I have not been on Reddit much, but I am sure they are doing great. Thank you for watching! 🙂

[@sabrinaschmid2260]

Wait the bishop cant be there 😂😂

[@ChessforCharity]

It is pretty cool! Thanks for watching!

[@judithcabanero]

It can :)

[@cniedbala87]

Holy hell

[@ChessforCharity]

🤣 Thank you for watching!

[@chainjail4834]

So en passant is like a back stab

[@ChessforCharity]

Haha, it is certainly an interesting rule.

[@NotPabu]

The position in the first puzzle is impossible to reach as black would need a way to get a double check with the bishop in the rook in that formation which is impossible to do with the king placed there, no matter where a rook or bishop was before. The king is legal on b3 but the position in question is not possible to reach.

[@ChessforCharity]

It may seem impossible, but this whole puzzle is showing that it is possible if the pawns and the king are placed properly. This is the beauty of the en passant rule. Thank you for watching! 🙂

[@NotPabu]

@@ChessforCharity But in the very first position, there arent any pawns on the board, and en passant doesnt get rid of both pawns

[@ChessforCharity]

@@NotPabu Yes, that is why the king is on c3 in the initial position. En passant got rid of the white pawn and then the white king captured the black pawn on c3. It is a pretty cool puzzle! ♟

[@NotPabu]

@@ChessforCharity But how than did the king capture the pawn on c3, if it was covered by at least 1 piece? Black would have to move next and somehow get a double check with the rook and bishop in the formation that they are in, which is impossible, so a black piece had to already be covering c3 prevent white from recapturing the pawn on c3

[@NotPabu]

@@ChessforCharity oh wait nevermind I just look idiotic 😅

[@ramble21]

b3

[@ChessforCharity]

You are close!

[@ramble21]

@@ChessforCharity oh i meant c3, that was a typo lol

[@ChessforCharity]

@@ramble21 then you were right! Thank you for watching!

[@vverbov22]

...or a3

[@Luca-pd6bq]

a3 is not possible. He clearly explained that...

[@ChessforCharity]

It may seem like it, but a3 does not work. It is super tricky! Thank you for watching!

[@honestwong8942]

The final position does not have a pawn, so the king must have captured it on c3

[@ggeshundra]

worst puzzle ever

[@Luca-pd6bq]

Greatest puzzle ever. What is so bad about it?

[@ChessforCharity]

I respectfully disagree. I think that being able to look back in the position using pure logic to find the *one* square for the king is quite amazing. That is just my opinion though. I appreciate you watching and hope you enjoy some of my other puzzles. 🙂

[@ggeshundra]

@@Luca-pd6bq i couldnt solve it

[@ggeshundra]

@@ChessforCharity okay