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View Full Version : It took Kasparov some long minutes to solve this!



Javier Gil
10-02-2004, 09:25 PM
rnbqkbnr/pp3ppp/2p1p3/8/4P3/8/PPPP1PPP/RNBQK1NR w KQkq - 0 5

Apparently, this position was shown to Kasparov and it took him many long minutes to work out the solution.
The position is reached after black's 4th move. It can be done in 3 moves or 5, that's easy, but how do you reach the position after black's 4th move? that's a little harder!

Good luck!

By the way, if you know the answer, don't post it, just say that you do and let others think about it for a while. :)

Kevin Bonham
13-02-2004, 03:38 AM
Got it. Took me ages though (over half an hour) :(

booboo
15-02-2004, 11:07 PM
OK I've thought about it for a while...and a while...and a while. I can get it in 3 moves, in 31/2 moves, in 41/2 moves and 5 moves, BUT NOT IN 4 MOVES.
I might just ask Kasparov

Kevin Bonham
15-02-2004, 11:39 PM
That's the annoying thing about it. 3.5 moves is soooooo easy.

A small hint: don't try just playing moves and looking at random for a solution. Try to think logically about what each side's moves, as a whole, must include or may include.

jase
16-02-2004, 12:17 AM
Well it took me a couple of minutes, but I don't think I'm quite ready to take on Kaspy just yet. To be honest I usually suck at these sorts of puzzles.

Good to see you're still taking an interest in the local scene here Javier...hope all is well and with some luck we will both be in Menorca later in the year :owned:

JGB
20-02-2004, 09:44 PM
Does it have to be logical play. I wouldnt think so or white would not have lost a B for a pawn. I found it easy in just a few minutes, im thinking i may have the problem not correctly understood, but i have the position after 4 moves.

Im normally nothing special at these questions but I am waiting for the solution to see if I was correct.

Thanks, James.

Kevin Bonham
21-02-2004, 12:50 AM
Does it have to be logical play.

No, any legal moves will do so long as you get the position after Black's 4th move. Unique solution AFAICT.

ursogr8
21-02-2004, 02:07 PM
That's the annoying thing about it. 3.5 moves is soooooo easy.

A small hint: don't try just playing moves and looking at random for a solution. Try to think logically about what each side's moves, as a whole, must include or may include.

Kevin

Michael Kontorovich solved it for me in 23 seconds. I went gasp until he told me he saw it in a book in 1972. Seems that Michael spent 6 years at the Tchigorin palace in St Petersberg being trained by Taimanov.

The 'mentor' from the Fischer_random was completely unable to make headway; but his 10 year-old-junior got close in 10 minutes.
Our web-master is a Physicist and saw the theme of the solution by working out the 'parity' implication of thinking c6 and e6 and capture were moves that had to be played.

Booboo had given up waiting for Kasparov to call.

starter

Kevin Bonham
21-02-2004, 10:11 PM
Our web-master is a Physicist and saw the theme of the solution by working out the 'parity' implication of thinking c6 and e6 and capture were moves that had to be played.

Yes - although this is not immediately obvious. One notices quickly that there must be either four black pawn moves or two, because otherwise a black piece would have moved once, which is impossible. But then one has to eliminate the four black pawn move possibility. In theory, either c6 or e6 could be the original d-pawn, with either the original c-pawn or the original e-pawn moving twice then getting taken. But in practice, this can't be made to work. I spent far too much time working through this, but at least I satisfied myself that the solution is unique in the process. :eek:

There should be more than enough hints now for anyone still struggling.

Trent Parker
09-03-2004, 04:33 PM
:doh: :wall: Okay Call me thick. I still have not found the answer.

Lucena
04-05-2004, 05:06 PM
:doh: :wall: Okay Call me thick. I still have not found the answer. well I wouldn't be to worried if I were you. i tend to find these sort of positions rather nasty at the best of times and quite removed from actual chess play. btw, is someone going to post the solution in case someone wants the answer?

arosar
04-05-2004, 05:29 PM
Have youse tried your nuggin at the de Groot problem?

AR

Lucena
04-05-2004, 05:43 PM
Have youse tried your nuggin at the de Groot problem?

AR

no what's that? and it's a "noggin" isn't it?

JGB
05-05-2004, 07:51 PM
Javier, are you going to post a reply for those who havent got it?

Lucena
12-05-2004, 11:30 AM
Javier, are you going to post a reply for those who havent got it?

I guess I'm going to have to work it now so some answers actually get posted :doh:

ursogr8
12-05-2004, 12:01 PM
I guess I'm going to have to work it now so some answers actually get posted :doh:

Kevin's post #9 tells all.

Lucena
14-05-2004, 09:06 PM
Kevin's post #9 tells all.

I disagree. Even with his hints it's still not that simple to work out. It takes a bit of effort to realise that the piece that's moved twice is the Black king and how it has captured the White bishop. For the benefit of anyone who wants the solution(and I think it's been well and truly long enough now), it's 1. e4 e6 2. Bb5 Ke7 3. Bxd7 c6 4. Be8 Kxe8. Kind of cute.

ursogr8
15-05-2004, 09:01 PM
I disagree.

Before I pointed you back to KB's post you said you could not solve. After reading the post, you now can solve. What part of 'tells' all' is still missing?

starter

Rincewind
15-05-2004, 11:44 PM
Before I pointed you back to KB's post you said you could not solve. After reading the post, you now can solve. What part of 'tells' all' is still missing?

I too think 'tells all' is overstating it. Kevin's post puts you on the right path but falls well short of telling all.

ursogr8
16-05-2004, 07:43 AM
I too think 'tells all' is overstating it. Kevin's post puts you on the right path but falls well short of telling all.

Nicely put Baz. You have a way with words. ;)

Can you put that 'way' to good effect by describing which bit is still missing. Otherwise it is ALL to me. :uhoh:

The meaning on 'Tell all' seems to rest on whether one has to provide 100% content (your view I think) or 'sufficient' content so that the requestor can work out 100% of the answer (my view).

starter

Lucena
16-05-2004, 10:27 PM
I too think 'tells all' is overstating it. Kevin's post puts you on the right path but falls well short of telling all.

That's what I meant.

Lucena
16-05-2004, 10:29 PM
Nicely put Baz. You have a way with words. ;)

Can you put that 'way' to good effect by describing which bit is still missing. Otherwise it is ALL to me. :uhoh:

The meaning on 'Tell all' seems to rest on whether one has to provide 100% content (your view I think) or 'sufficient' content so that the requestor can work out 100% of the answer (my view).

starter

well someone's trying to do some semantic acrobatics here :D

Rincewind
16-05-2004, 11:09 PM
well someone's trying to do some semantic acrobatics here :D

Well spotted. Starter's position is unteniable since the stating the puzzle itself gives all the information necessary to "work out 100% of the answer". Therefore, the wording of all good puzzles "tell all" by defintion.

You can take that sematic position of course, but it is not what most people take "KB posts tells all" to mean.

I think Kevin's post just provides some hints that one could deduce from the puzzle without knowing the solution. Therefore it provides a indication as to where the puzzle's solution might lie, but doesn't give you its exact location.

"Telling all" would be more along the lines of: The King captures the Bishop on e8. While that isn't strictly speaking telling all, it certain crosses the line from hint to spoiler. Also it cannot be easily deduced from the puzzle without knowing the exact solution.

ursogr8
17-05-2004, 08:27 AM
well someone's trying to do some semantic acrobatics here :D

hi garethbcharles and baz

Experienced puzzlers and experienced BB helpers know that it is polite to not post a 'recipe solution', but rather to post 'sufficient information' to allow the stumped puzzler to move forward.
That is what KB did.
He showed which part of the incorrect assumptions made by unsuccessful puzzlers (of this particular puzzle) needed to be reversed. Once the false assumption is discarded then both of you are good enough puzzlers to move to the answer (as garethbcharles has).

Next time, if you want recipe solution then ask for a recipe; otherwise you are likely to get hints.

BTW, which part of ALL are you still missing?

starter

ursogr8
17-05-2004, 08:37 AM
Well spotted. Starter's position is unteniable since the stating the puzzle itself gives all the information necessary to "work out 100% of the answer". Therefore, the wording of all good puzzles "tell all" by defintion.

.

Baz

There is a difference between the two 'puzzles' as presented in this thread. The first puzzle was a diagram and a challenge to solve in a specified number of moves. That puzzle obviously seduced an assumption in most puzzlers (who have chess intuition), and the assumption needs to be rejected to move forward. The breaking of the assumption and new attempts at the 're-defined' problem taxes the patience of most....hence the problem becomes difficult to solve. So, clearly the original problem does not TELL ALL because the solution is not reached by garethbcharles.

The second puzzle has the false assumption stripped away (by KB's hint). This is enough for garethbcharles. He has been TOLD ALL.

starter

ps Obviously we agree that a 'recipe' TELLS ALL. What we appear to be debating is whether a hint TELLS ALL.
And further, the hint will only be useful to some puzzlers. In this case the hint was sufficient for garethbcharles.

Rincewind
17-05-2004, 10:17 AM
Starter,

different solvers will have different opinions as to the crux of the puzzle. For me, I don't think KB's hint disclosed the crux of the puzzle, if that were the crux the puzzle would be much simpler than it is. To tell all, one has to give away the crux, therefore KB's post did not tell all.

BTW regarding your comparison of hint vs recipe. Saying "the King captures the Bishop on e8" is not a recipe solution but does (I think) give away the crux of the puzzle. Regarding the numer of pawn and piece moves that Black makes is just an indication of the general direction in which to look. There are still a number of pieces and various order of pawn moves for the puzzler to sift through before finding the solution.

ursogr8
17-05-2004, 10:54 AM
Starter,

different solvers will have different opinions as to the crux of the puzzle. For me, I don't think KB's hint disclosed the crux of the puzzle, if that were the crux the puzzle would be much simpler than it is. To tell all, one has to give away the crux, therefore KB's post did not tell all.

BTW regarding your comparison of hint vs recipe. Saying "the King captures the Bishop on e8" is not a recipe solution but does (I think) give away the crux of the puzzle. Regarding the numer of pawn and piece moves that Black makes is just an indication of the general direction in which to look. There are still a number of pieces and various order of pawn moves for the puzzler to sift through before finding the solution.

hi Baz.
Interesting that you introduce the new word crux to our discussion.
My first inclination is that crux is like 'part-of-the-recipe'. Is that your intention?

But a hint can be something quite different from 'part-of-the-recipe'. For example in this chess puzzle, a few at BHCC have been able to solve after the hint 'discard your assumption about which of two pawn moves is first by Black'. Clearly this hint is not part of the 'recipe'. But it does assist in finding the solution.
Another player spent quite a few hours on a fruitless search and arrived at the Club convinced the problem was faulty. When we assured him a solution was known he found it in 14 minutes. In this case, the 'hint' was not even a chessic statement; but simply a confirmation that a solution exists and that the solver should approach the problem with confidence.

starter

ursogr8
17-05-2004, 10:57 AM
Starter,

For me, I don't think KB's hint disclosed the crux of the puzzle.

But it obviously did for g..charles, Baz. He went from not-solving to solving.

starter
ps And remember, my TELL ALL was directed to g..charles. (And I had guessed that he was a strong player). I did not intend my hint to be TELLS ALL for other solvers.

Rincewind
17-05-2004, 12:04 PM
Interesting that you introduce the new word crux to our discussion.
My first inclination is that crux is like 'part-of-the-recipe'. Is that your intention?

No, the term is already established usage in puzzle solving and just refers to the part of the solution which is the most difficult to find. The form of the hint which gives away the crux may be of any form, recipe-like or otherwise.


But a hint can be something quite different from 'part-of-the-recipe'. For example in this chess puzzle, a few at BHCC have been able to solve after the hint 'discard your assumption about which of two pawn moves is first by Black'. Clearly this hint is not part of the 'recipe'. But it does assist in finding the solution.

Yes, hints can take many forms. However, I still contend KB clues did not give away the crux. I think to "tell all", the crux must be given away or else the hardest part of the puzzle remains to be solved.


Another player spent quite a few hours on a fruitless search and arrived at the Club convinced the problem was faulty. When we assured him a solution was known he found it in 14 minutes. In this case, the 'hint' was not even a chessic statement; but simply a confirmation that a solution exists and that the solver should approach the problem with confidence.

Knowledge that the puzzle is well-formed and no misunderstanding of the puzzle has taken place helps greatly with searching for the solution, in terms of motivation. However, that is not strictly speaking a hint. However, if the requirements are reworded there is a chance that a hint may unintentionally slip.

The philosophical side of puzzles is facinating in its own right. However, regarding our disagreement, I think the bone of contention is whether KB post gave up the crux. One's position will depend on where you believe the crux of the puzzle to lie. To my mind it is the king taking the bishop on e8 which is the crux, and by that definition KB's hint does not "tell all".

Rincewind
17-05-2004, 12:09 PM
But it obviously did for g..charles, Baz. He went from not-solving to solving.

No, it didn't. It just told him in which direction to look. Gareth still had to find the Be8 Kxe8 manoeuvre himself. Just as solvers who found this manoeuvre from Gil's original email were not told all by the simple wording of the puzzle. This is the flaw with your position. The fact that the hint lead the person to solutoin does not mean that hint told all.

ursogr8
17-05-2004, 12:29 PM
No, the term is already established usage in puzzle solving and just refers to the part of the solution which is the most difficult to find. The form of the hint which gives away the crux may be of any form, recipe-like or otherwise.

Ok. I am comfortable if you want this definition.







Yes, hints can take many forms. However, I still contend KB clues did not give away the crux. I think to "tell all", the crux must be given away or else the hardest part of the puzzle remains to be solved.



Yes, but Barry; I did not say it was in Kevin’s clues. I said it was in Kevin’s post. And that included the quote
“of thinking c6 and e6 and capture were moves that had to be played “.

My experiences with solvers is that this is the crux.
But if you found Be8 to be the crux then fair enough.







Knowledge that the puzzle is well-formed and no misunderstanding of the puzzle has taken place helps greatly with searching for the solution, in terms of motivation. However, that is not strictly speaking a hint. However, if the requirements are reworded there is a chance that a hint may unintentionally slip.

The philosophical side of puzzles is facinating in its own right. However, regarding our disagreement, I think the bone of contention is whether KB post gave up the crux. One's position will depend on where you believe the crux of the puzzle to lie. To my mind it is the king taking the bishop on e8 which is the crux, and by that definition KB's hint does not "tell all".



Can I say ‘Alls well that ends well’?

starter

Kevin Bonham
17-05-2004, 10:14 PM
Hmmm, this is almost as good as the inaugural goosefest in which Bill and chesslover debated whether I had called chesslover a goose or not for several dozen posts. :rolleyes:

Bill Gletsos
17-05-2004, 11:00 PM
Hmmm, this is almost as good as the inaugural goosefest in which Bill and chesslover debated whether I had called chesslover a goose or not for several dozen posts. :rolleyes:
Which you clearly had. ;)

ursogr8
18-05-2004, 08:03 AM
Hmmm, this is almost as good as the inaugural goosefest in which Bill and chesslover debated whether I had called chesslover a goose or not for several dozen posts. :rolleyes:

KB

Ah. But there is a difference.

Chesslover's whatever-it-could-be-called with Bill had no crux, whereas our erudite discussion clearly found the id. of the crux was the root-cause of the different views.

starter

ps So KB, that leads me to describe their whatever-it-could-be-called as just Cruxless panting.

Lucena
18-05-2004, 10:00 PM
ps So KB, that leads me to describe their whatever-it-could-be-called as just Cruxless panting.

That is sooooooooooo not funny :hand: :rolleyes: :wall:

Bill Gletsos
18-05-2004, 10:27 PM
KB

Ah. But there is a difference.

Chesslover's whatever-it-could-be-called with Bill had no crux, whereas our erudite discussion clearly found the id. of the crux was the root-cause of the different views.

starter

ps So KB, that leads me to describe their whatever-it-could-be-called as just Cruxless panting.
Well it is obvious who is having himself on here.
What a goose. :whistle:

ursogr8
25-05-2004, 01:01 PM
Well it is obvious who is having himself on here.
What a goose. :whistle:

hi Bill

Not your normal friendly post by you?
Let me guess, you have not solved the puzzle yet, even after the hints? :(

starter

Bill Gletsos
25-05-2004, 01:07 PM
hi Bill

Not your normal friendly post by you?
Well you and your crux were having yourself on. ;)


Let me guess, you have not solved the puzzle yet, even after the hints? :(
I worked it out just before Kevin posted his hints.
In fact my logic was very similar to his.

hitman84
06-12-2005, 03:19 AM
good one !! it took me 5 min

hitman84
06-12-2005, 04:44 PM
A very nice problem but somebody posted the clue which made it very simple-"tellall"
if you find out the fourth move the rest is a walk in the park!