Chess will never be solved, here's why

@7093

"Final position has 10 men. In which 7 man tablebase did they look up the draw?"
++ Recapture Kxf2 is forced, then Rf6+ and Rxf7

None of which is forced. Admit it you just couldn't count up to 7 - still can't coz that's 8. (And I'm sure ICCF rules say you've got to reach the 7 man tablebase before you can claim.)

++ If you start analysing chess then you hit a 7-men endgame table base draw after 33 moves i.e. 66 ply in some branches of optimal play by both sides; after 44 moves i.e. 88 ply in half of the branches; after 60 moves i.e. 120 ply most of the branches and after 120 moves i.e. 240 ply all branches.

What on Earth are you talking about?

Chess never reaches the 5898.5 move maximum: that is by 49 useless moves hopping around, then a 1 step pawn move, then 49 useless moves hopping round etc.
After 120 moves of perfect play the game ends in a draw in all branches.

You could be right. But how does that relate to your proposed method of solution? Stockfish doesn't do perfect play.

But Syzygy does.

"Mine was faster anyway." ++ But yours was no optimal play from both sides.

99.9 % of my games are perfect. Got that off the big red telephone to the Gent upstairs, same way you got your ICCF stats.

That's the trouble with videos. It's not. It's 8848.5.

Read the link.

(They probably meant 5899 anyway, or 5898.5 at any rate, depending on how you look at it.)

@7107

"What on Earth are you talking about?" ++ This is the longest perfect game with optimal play from both sides to reach the 7-men endgame table base draw.
https://www.iccf.com/game?id=1164280 
It took 119 moves to the 7-men endgame table base draw i.e. 238 ply. All the other perfect games reach the 7-men endgame table base draw or a prior 3-fold repetition sooner.

"But how does that relate to your proposed method of solution?"
++ If you calculate all reasonable white moves, then 1 tentative black response, then all reasonable white moves, then 1 tentative black response and so on then the 7-men endgame table base draw or a prior 3-fold repetition is reached in at most 119 moves, i.e. 238 ply.

Another explanation: chess has 10^44 legal positions. 10^44 = 2^146.
So after 146 digital decisions you get the whole of Chess.
Checkmates that exceed 146 moves exist, but they must contain a string of forced moves.

"Stockfish doesn't do perfect play."
++ Agreed, but that does not matter. Stockfish only needs to generate the reasonable white moves. Stockfish then selects the 1 black response without worry if perfect or not.
If a 7-men endgame table base draw or a prior 3-fold repetition is reached, then that validates all black responses as fit to draw.

"99.9 % of my games are perfect" ++ No, they are not.

"same way you got your ICCF stats." ++ No.

@7094

"So how can a group of GMs (smokers or not) be expected to recognize perfect play?"
++ They do not, and they do not need to: it is the 7-men endgame table base that pronounces the verdict. If whatever you try for white leads to a 7-men endgame table base draw or a prior 3-fold repetition, then Chess is weakly solved.

"How can we rely on their decisions as to which lines to ignore?" ++ That is why they need to be (elder) (ICCF) (grand)masters. They only ignore lines they are sure of like 1 e4 e5 2 Ba6?

"By the time this five-year "solution" process is complete it will be out of date."
++ No. Without any human intervention and only limiting underpromotions to pieces previously captured it would require Sqrt(10^38) = 10^19 positions i.e. 500 years to weakly solve Chess.
The game knowledge of the good assistants cuts it down to 10^17 positions and 5 years. 

"no way Sveshnikov's plan will produce a definitive solution" ++ The only problem is funding.

"a brute force calculation of all possible lines, from the opening position to a hopeless draw"
++ It can be accomplished with 3 cloud engines and 3 (elder) (ICCF) (grand)masters.

"as has been repeatedly demonstrated here" ++ I have repeatedly demonstrated it can be done.

"I hardly expect to live to witness such an outcome."
++ It depends on funding. Maybe you will live when humans walk on Mars, maybe not.

@7112

"analysis will done on only those opening moves the experts consider relevant"
++ Analysis will not be done on moves that are clearly no optimal play e.g. 1 e4 e5 2 Ba6, 1 e4 e5 2 Nf3 Nc6 3 Ng5 etc. It is to not waste engine time on what is already obvious.

"will only analyze lines from drawn ICCF grandmaster games"
++ The drawn ICCF WC Finals games serve as a backbone of already completed analysis as they each already represent 2 years of engine analysis under guidance of an ICCF grandmaster.
It is to speed up the process.

"This seems to make the entire enterprise reliant on humans and engines that are known to be imperfect." ++ The enterprise relies on the 7-men endgame table base known to be perfect.

"Am I misunderstanding something?" ++ Yes

Stockfish - "I am not 100% sure about the move 2. Ba6. Better investigate it a little. Still won't be absolutely sure, but this is essential for practical purposes".

@tygxc - "I can just look at 1. e4 e5 2. Ba6 and know with 1 ply analysis what the result is."

Stockfish - "I guess that's why I'm 1500 Elo points stronger than you".

@7107

"What on Earth are you talking about?" ++ This is the longest perfect game with optimal play from both sides to reach the 7-men endgame table base draw.
https://www.iccf.com/game?id=1164280 

No it's not.

It's Jon Edwards v Sergey Adolfovich Osipov from the ICCF WC 32, which ended in an agreed draw with 13 men on the board.

This is the same game continued using Arena/Stockfish. It ended with a claim under the 50 move rule on move 236.

It took 119 moves to the 7-men endgame table base draw i.e. 238 ply.

You may as well leave out the endless translations from moves to ply; I think we can all manage it. Especially since you appear to have insurmountable problems counting up to 7.

All the other perfect games reach the 7-men endgame table base draw or a prior 3-fold repetition sooner.

Big red telephone again, right?

"But how does that relate to your proposed method of solution?"
++ If you calculate all reasonable white moves, then 1 tentative black response, then all reasonable white moves, then 1 tentative black response and so on then the 7-men endgame table base draw or a prior 3-fold repetition is reached in at most 119 moves, i.e. 238 ply.

You don't have a reasonable definition of "reasonable".

You claim that all perfect games that are not Jon Edwards v Sergey Adolfovich Osipov from the ICCF WC 32 reach the 7-men endgame table base draw or a prior 3-fold repetition sooner than Jon Edwards v Sergey Adolfovich Osipov from the ICCF WC 32. That's true of perfect games that reach one or other, but only because Jon Edwards v Sergey Adolfovich Osipov from the ICCF WC 32 never reached either. 

But perfect games need only perfect moves, they don't have to include moves that tygxc thinks are reasonable. You make no connection between perfect moves and moves that tygxc thinks are reasonable.

Indeed, earlier in the thread you accused the Syzygy tablebase of trolling in this game.

Is it your contention that Syzygy is trolling and all it's moves are reasonable?

Another explanation: chess has 10^44 legal positions. 10^44 = 2^146.

Here you're a victim of your own misinformation.

Tromp's estimate of the number of basic rules positions is 4.82 x 10^44.  NOT 10^44. 

2^148 < 4.82 x 10^44 <2^149.
So after 146 digital decisions you get the whole of Chess.

By "digital decisions" I assume you mean choices of moves. (Or are you still struggling to count up to 7 on your fingers?)

You make no mention of whether or not the moves are perfect so the continuation of Jon Edwards v Sergey Adolfovich Osipov would be a case in point.

I can't find anywhere in that game the position after 1.e4 e5 2.Ba6. Can you? Wouldn't that be included in Chess?

Neither can I find any of the large number of positions with the same diagram and ply count, say, 13 under the 50 move rule. Would they not also be included in Chess (though of course not in Tromp's number)? 
Checkmates that exceed 146 moves exist, but they must contain a string of forced moves.

So far as I can understand your logic (not very far), that seems to rest on on the obviously invalid assumption that the number of basic rules positions associated with the competition rules positions occurring in all continuations is the product of the number of choices of moves in each such competition rules position or something of the sort. Choice of perfect moves maybe?

That would need Tromp's upper bound rather than his estimate for a valid proof (as well as a different argument). Also you would need to say exactly what you mean by "forced" and how many moves constitute a "string". (Do you include strings of one?.)

Here is a provably perfect (just in case it needs to be) checkmate in 148. Can you indicate some strings of forced moves?

Mainly, I can't see your point even if what you say is true. It is to be expected that with most definitions of "forced move" such strings will occur in a long sequence of moves whether as part of a win or draw. Are you trying to make a relevant point or are you just away wi' the fairies? 

Edit: sentence reinserted for context ->But how does that relate to your proposed method of solution? "Stockfish doesn't do perfect play."
++ Agreed, but that does not matter. Stockfish only needs to generate the reasonable white moves.

In the vanishingly unlikely event that you ever got a sponsor it might matter to him.

How are you going to make it generate only moves tygxc thinks are reasonable?

Stockfish then selects the 1 black response without worry if perfect or not.
If a 7-men endgame table base draw or a prior 3-fold repetition is reached, then that validates all black responses as fit to draw.

Obviously not.

"99.9 % of my games are perfect" ++ No, they are not.

Are so !

"same way you got your ICCF stats." ++ No.

++Yes. So there !

@7116

"which ended in an agreed draw with 13 men on the board"
++ The transition to a 7-men endgame table base draw is forced.

You just shovel the s*** on don't you. 

You have it off the big red telephone that neither side can resign, checkmate or force a triple repetition or dead position before the material reduces to 7 men. How does that affect my statement that the game you linked to doesn't prove that the maximum length perfect game is 119 moves?   

"This is the same game continued using Arena/Stockfish." ++ Very well, this shows the need for human assistants to cut short such needless calculations and call it a draw.

Again, how does that affect my statement that the game you linked to doesn't prove that the maximum length perfect game is 119 moves? Why change the subject?  

"All the other perfect games reach the 7-men endgame table base draw or a prior 3-fold repetition sooner. Big red telephone again?"
++ No, statistics. Between 13 and 119 moves, 42 moves average, with standard deviation 16.

Bad statistics. Not even showing statistically that there's a small probability of a perfect game longer than 119 moves.

If you were to apply your oft cut and pasted analysis to the games shown here and use your previously stated assumptions, you should come to the conclusion that the most probable size of your sample of perfect games from ICCF WC 32 is 0. Why don't you try it?

You can't do much useful statistics with a sample size of 0.

Even if you assumed they were all perfect, it would be interesting to see what you would assign as the probability that there were no longer perfect games in the whole of chess.

I'm sure you could make it 10^17 %. Go on. Give it a go!

"If you calculate all reasonable white moves, then 1 tentative black response, then all reasonable white moves, then 1 tentative black response and so on then the 7-men endgame table base draw or a prior 3-fold repetition is reached in at most 119 moves, i.e. 238 ply.
You don't have a reasonable definition of reasonable".
++ That is just the best first heuristic as used in solving Checkers and Losing Chess.
If the 4 best moves cannot win for white, then the worst moves cannot win either.

By which, I take it, you still don't have a reasonable definition of "reasonable".

"But perfect games need only perfect moves"
++ Statistics applied to the ICCF WC Finals games show they are > 99% sure to be perfect games i.e. they contain optimal moves from both sides.

Only when you apply them, but statistics is obviously not your strong point.

"Tromp's estimate of the number of basic rules positions is 4.82 x 10^44"
Yes, but the factor 4.82 is irrelevant and should be 1.205 because of up / down symmetry and left / right symmetry after loss of castling rights.

The factor 4.82 is relevant because in ignoring it you arrive at the conclusion, "so after 146 digital decisions you get the whole of Chess", whereas if you had not ignored it you might have arrived at, "so after 149 digital decisions you get the whole of Chess", which would have been closer to what you had intended (albeit still flagrant nonsense).

More to the point others may make similar mistakes if you keep posting misrepresentations of Tromp's figure.

It shouldn't be reduced to 1.205 ^10^44 because "the whole of Chess" doesn't mean one position in four.

"2^148 < 4.82 x 10^44 <2^149" ++ Yes

"By digital decisions I assume you mean choices of moves"
++ Yes, less than 149 choices between 2 moves, or less than 74 choices between 4 moves.

For a proof you'ld need an upper bound, not an estimate. More to the point you'ld need a valid argument. Among other things some explanation of why you're using figures for basic rules positions in the context of competition rules.

"You make no mention of whether the moves are perfect or not"
++ That is only legal choice, if they need to be perfect there is even less choice.

"I can't find anywhere in that game the position after 1.e4 e5 2.Ba6. Can you?"
++ It is clear that 2 Ba6? is not optimal play by white.

How is that remotely relevant? Your statement was, "So after 146 digital decisions you get the whole of Chess" (optimal or not, presumably).

"Wouldn't that be included in Chess?" ++ Yes, 1 e4 e5 2 Ba6? belongs to the 10^44 legal positions, but not to the 10^17 relevant positions.

How is that remotely relevant? Your statement was, "So after 146 digital decisions you get the whole of Chess" (included in your silly subset or not, presumably).

"Neither can I find any of the positions with the same diagram and ply count 13 under the 50 move rule" ++ The 50-moves rule plays no role.

The 50 move rule plays no role in your head, but it does in chess under FIDE competition rules. It says so in the handbook.

Moves that could draw under the triple repetition rule from the ply count 13 positions would not draw from the ply count 3 position. 

Games with optimal play from both sides end in draws long before the 50-moves rule would trigger.

Another tip from the big red telephone? You still haven't realised that He feeds you BS because He knows you're not going to listen to a damn word anyway.

How do you define "optimal"?

"How are you going to make it generate only moves tygxc thinks are reasonable?"
++ Stockfish ranks the legal moves. Then it is the best first heuristic.
If the best white moves cannot win, then the worse white moves cannot win either.

So how are you going to make it generate only moves tygxc thinks are reasonable?

"If a 7-men endgame table base draw or a prior 3-fold repetition is reached,
then that validates all black responses as fit to draw."

Obviously not.

++ People here still fail to understand this, though it is simple.
If all reasonable white moves fail to win against a black response, then that black response is optimal. It does not matter how that black response was obtained. It does not matter if other black responses draw as well or not.
If white cannot win against those black responses, then Chess is weakly solved.
If the black responses lead to a table base draw or a prior 3-fold repetition,
then they are optimal in retrospect.

It is simple or you are simple?

If all White moves fail to win against a Black response, but succeed in drawing, while all White moves against some different Black responses lose, most rational people would say that Black response is not optimal. 

@7112

"analysis will done on only those opening moves the experts consider relevant"
++ Analysis will not be done on moves that are clearly no optimal play e.g. 1 e4 e5 2 Ba6, 1 e4 e5 2 Nf3 Nc6 3 Ng5 etc. It is to not waste engine time on what is already obvious.

"will only analyze lines from drawn ICCF grandmaster games"
++ The drawn ICCF WC Finals games serve as a backbone of already completed analysis as they each already represent 2 years of engine analysis under guidance of an ICCF grandmaster.
It is to speed up the process.

"This seems to make the entire enterprise reliant on humans and engines that are known to be imperfect." ++ The enterprise relies on the 7-men endgame table base known to be perfect.

"Am I misunderstanding something?" ++ Yes