Chess will never be solved, here's why

Not really, because after 5 years @tygxc would probably be sitting beneath palm trees on a sunny beach and impossible to contact.

If you are interested in commissioning me, I will be designing a quantum computer to do a strong solution.

Seriously, that is currently beyond the capabilities of humans (still more me) but at least it makes sense conceptually.

@6677

"We do know. There are only 10^44 legal positions, the vast majority of them stupid.
Now 10^44 = 2^146. So even if there are only 2 choices per move, 146 moves exhaust the number of legal positions. Checkmates with more than 146 moves must contain a string of forced only moves for the defending side. "

But you don't know that, and that is the whole reason why it would take a quantum computer to solve chess on a 8x8 board and thats what it means that 8x8 Chess is an EXP decision problem. It can easily be assumed that through pruning the four "known best moves" will lead to the best outcome but you literally can't say that because its not a guarantee that White will win if both sides play perfectly. You are talking about machine learning and through pruning you can reach 99% accuracy but unless you go through the entire decision tree of possible moves you could never know.  Those four best known moves you are talking about are only based on the data we have now. Also I am a bit confused what you mean by "146 moves exhausts all the moves", https://www.chess.com/forum/view/endgames/who-wins-from-this-puzzle , right there is a thread of a game in the 7-move tablebase that takes 546 moves to play perfectly.

To put it right I think, 8x8 chess is in EXP time and generalized chess are in EXP-Complete time, both are solvable but they require an exponential amount of time to do it. Thus it would take a quantum computer to do it because the numbers are so vast, but the game is definitely "solvable". I think looking at your post that we agree that it is solvable, but definitely not through your method of pruning the data, because in essence all the data you have to "prune" is our training data. We do not know the whole thing, I think Claude Shannon, a renowned computer scientist can put it better than I can.

"These two facts imply (von Neumann and Morgenstern, 1944) that any given position of the chess pieces must be either: -

(1)A won position for White. That is, White can force a win, however Black defends.
(2)A draw position. White can force at least a draw, however Black plays, and
likewise Black can force at least a draw, however White plays. If both sides play
correctly the game will end in a draw.
(3)A won position for Black. Black can force a win, however White plays.
This is, for practical purposes, of the nature of an existence theorem. No practical method
is known for determining to which of the three categories a general position belongs. If
there were chess would lose most of its interest as a game. One could determine whether
the initial position is a won, drawn, or lost for White and the outcome of a game between
opponents knowing the method would be fully determined at the choice of the first move.
Supposing the initial position a draw (as suggested by empirical evidence from master
games [1]) every game would end in a draw."

"We do know. There are only 10^44 legal positions, the vast majority of them stupid.
Now 10^44 = 2^146. So even if there are only 2 choices per move, 146 moves exhaust the number of legal positions. Checkmates with more than 146 moves must contain a string of forced only moves for the defending side. "

But you don't know that, and that is the whole reason why it would take a quantum computer to solve chess on a 8x8 board and thats what it means that 8x8 Chess is an EXP decision problem. It can easily be assumed that through pruning the four "known best moves" will lead to the best outcome but you literally can't say that because its not a guarantee that White will win if both sides play perfectly. You are talking about machine learning and through pruning you can reach 99% accuracy but unless you go through the entire decision tree of possible moves you could never know.  Those four best known moves you are talking about are only based on the data we have now. Also I am a bit confused what you mean by "146 moves exhausts all the moves", https://www.chess.com/forum/view/endgames/who-wins-from-this-puzzle , right there is a thread of a game in the 7-move tablebase that takes 546 moves to play perfectly.

To put it right I think, 8x8 chess is in EXP time and generalized chess are in EXP-Complete time, both are solvable but they require an exponential amount of time to do it. Thus it would take a quantum computer to do it because the numbers are so vast, but the game is definitely "solvable". I think looking at your post that we agree that it is solvable, but definitely not through your method of pruning the data, because in essence all the data you have to "prune" is our training data. We do not know the whole thing, I think Claude Shannon, a renowned computer scientist can put it better than I can.

"These two facts imply (von Neumann and Morgenstern, 1944) that any given position of the chess pieces must be either: -

(1)A won position for White. That is, White can force a win, however Black defends.
(2)A draw position. White can force at least a draw, however Black plays, and
likewise Black can force at least a draw, however White plays. If both sides play
correctly the game will end in a draw.
(3)A won position for Black. Black can force a win, however White plays.
This is, for practical purposes, of the nature of an existence theorem. No practical method
is known for determining to which of the three categories a general position belongs. If
there were chess would lose most of its interest as a game. One could determine whether
the initial position is a won, drawn, or lost for White and the outcome of a game between
opponents knowing the method would be fully determined at the choice of the first move.
Supposing the initial position a draw (as suggested by empirical evidence from master
games [1]) every game would end in a draw."

@6673

^^ And the reason why his quote his important is because like you said, if you knew a position was a given for white (what you think is e4, nf3, c4), the decision tree would be way smaller to exhaust through, but you DONT

I agree. He's not saying it would take a lot of time, money and effort. He's saying the opposite. He's saying it would take very, very little time, money, and effort. 

He's the only person I've ever seen that says solving chess is very, very easy. Very little time, very little money, and very little effort. I think if it were as easy as he says, it would have been done by now. Several times over. 

its because hes talking about machine learning methods. You train those on data and then use them to make accurate predictions, you can never be 100% sure of anything this way because you never have all the data necessary or its a chaotic system (in this case we are missing data) and once you do you wouldn't need a machine anymore cause everything could be logged in a table

@avramtparra

"Your chess is insane." avramtparra said, as he slipped his feminine hand into 6673's pants and smirked. "Are you trying to mate me?" protests 6673, as avramtparra blushes, the boyish figure undressed before 6673. "Weak tempo play, avramtparra." The two kissed, deeply and passionately, and afterwards 6673 places his Rook into avramtparra open line.

     tygxc's proposal is to start with only a handful of "best" opening moves, consider only lines played by world-class correspondence players (who use multiple engines' analyses in their games), employ a few GMs to judge what alternative moves to consider (or ignore). It may well be possible to come to some conclusions within the time and budget parameters he and Sveshnikov propose.

     The question is whether most people would consider such a solution a definitive proof.

     Of course that would be enough "proof" for some people. Not for you or me or most others here.

@DesperateKingWalk

That appears to be correct. 

The number is 152.65 and it's not a mate score.  I've just seen it come up in Arena/SF15 against a move that can't win (lots in fact).

@6721

"Very little time, very little money, and very little effort."
++ 5 years, 3 million $, 3 engines & 3 grandmasters is a long time, much money and effort.

"it would have been done by now" ++ People struggle to get a 100,000 $ loan to build a house, nobody has decided to shed 3 million $ with no payback. 

Not "no payback", surely.

5 years and 3 million would probably be enough to complete the 8-piece database and the 9-piece one. At that point, only 99.9999999999999999 percent of chess is left unsolved. Huge improvement!

@6717

"White will win if both sides play perfectly" ++ No, when both sides play perfectly it is a draw.

"unless you go through the entire decision tree of possible moves you could never know"
++ It is beneficial to incorporate game knowledge into game solving.
If the 4 best moves cannot win for white, then the 16 worst moves cannot win either.

"what you mean by 146 moves exhausts all the moves"
There are 10^44 legal positions. 10^44 = 2^146.
Thus a forced win of 546 moves must contain a string of forced moves by the defending side.
146 choices between 2 moves yields more positions than chess has legal positions.

"8x8 chess is in EXP time"
++ To strongly solve chess 10^44 legal positions need to be visisted.
That is beyond present capability. It might become possible with a quantum computer.
To weakly solve chess 10^17 relevant positions need to be visited.
That can be done with 3 powerful computers running for 5 years.
Many here still fail to understand the difference between strongly solving and weakly solving.

"your method of pruning the data"
++ It is not my method, it is the same method that Schaeffer used to weakly solve Checkers.

@6731

"5 years and 3 million would probably be enough to complete the 8-piece database"
++ An 8 men endgame tablebase strongly solves all 8-men positions.
5 years and 3 million $ are to weakly solve Chess, i.e. calculate from the initial position towards a 7-men endgame table base draw or a prior 3-fold repetition.

Well, quite a big improvement I would say.

Problem is @tygxc doesn't plan to use them for that. He plans to use them to not solve chess.

With the 50 move and triple repetition rules in force? What a quick learner you are! (Probably even right if your'e talking only about two kings and six bishops on the same coloured squares.)

Presumably you won't be generating any with unequal material because you already know those are wins for the side with the extra pawn or more. That dispenses with the great majority of 8 man tablebases and all the 9 man tablebases. In fact you don't actually need any tablebases, you can just stop when you've got 31 men. That should leave you with plenty of spare capacity to concentrate on the serious business of not solving chess.

hi

Yes, someone wrote, "++ An 8 men endgame tablebase strongly solves all 8-men positions" a few posts back.

Some even fail to understand the difference between solving and not solving.