Chess will never be solved, here's why

#3026

"If you say "there is no doubt", then it's 100% sure and thus proven."
++ When something is known, then there is no doubt, it is 100% sure, but the proof may not be available.

We know 1 e4 e5 2 Ba6? loses for white, there is no doubt, but there is no proof that works out all possible variations to checkmate. Proving it poses no problem, but it is not worthwhile to burn computer time on it, precisely because the outcome is not in any doubt.

Likewise we know 1 a4 is not superior to 1 d4 or 1 e4. Capablanca said so: 1 e4 and 1 d4 accomplish more than 1 a4. AlphaZero concurs. There is no doubt about it. It is 100% sure, but there is no proof available. Proving it is problematic in practice and nearly as demanding as proving 1 d4 and 1 e4 draw. However, once 1 d4 and 1 e4 are proven draws, then by the same methodology 1 a4 can be proven to draw too.

Likewise we know the opposite color bishop endgame is a draw and the ICCF grandmasters were right to agree on a draw. There would be no point in playing it out till a 3-fold repetition or a table base draw. If one of both had thought he had even the smallest chance of winning, then he would not have offered or declined the draw and they would have continued for months until all doubt was removed for both. 

Likewise we know the KRBPPPP vs. KRNPPPP endgame with symmetrical pawns on 1 wing is a draw and the ICCF grandmasters were right to agree on a draw. There would be no point in playing it out till a 3-fold repetition or a table base draw. If one of both had thought he had even the smallest chance of winning, then he would not have offered or declined the draw and they would have continued for months until all doubt was removed for both. 

#3027

"you assume it is infallible and think its knowledge is 100% reliable!"
++ No not at all, in fact I calculated its error rate at 60 h/move to be 1 error in 10^5 positions and thus concluded 4 white candidate moves are required to achieve 1 error in 10^20 positions.

"AlphaZero's "knowledge" has no different status to that of a chess player"
++ My point is that there are other sources of knowledge than computation. Chess knowledge by great human players and AlphaZero is valuable in its own right and per van den Herik is beneficial to incorporate in game solving. It is no match report of AlphaZero vs. Stockfish, it is a scientific paper that uses AlphaZero to acquire chess knowledge.

Likewise checkers was solved with the program Chinook.

Likewise humans have proven a lot about endgames. That is valuable knowledge and it is beneficial to incorporate that by truncating unnecessary calculations once a known drawn endgame >7 men is reached.

Weakly solving chess is a formidable task in itself. So all available help in reducing the calculation effort is needed. A purist attitude 'if it is not calculated by the computer then it is not true' is detrimental.

The more people question it, the surer you get.

#3029

"The move that it assesses to have a higher probability of a good result, it views as better."
++ Yes, that is correct, but the paper went further to evolve several versions of AlphaZero so as to acquire more and more dependable knowledge.

"It is sometimes wrong (to the extent that its decisions lose)."
++ Yes, at 60 h/move it errs in 1 out of 10^5 positions.

"And Capablanca is less reliable than AlphaZero."
++ No, that is like saying Euler is less reliable than Ramanujan.
Capablanca remarks that 1 e4 and 1 d4 occupy and control the center and open diagonals for the bishops and the queen and no other move accomplishes that much. All of that is true and verifyable and his conclusion is logical and true. AlphaZero independently came to the same conclusion and ranks 1 d4 and 1 e4 above all 18 other possibilities, just like Capablanca said. Personally I would consider chess weakly solved if 1 e4 and 1 d4 are proven draws. To be extra sure I would also include 1 c4 and 1 Nf3 (top 3 and top 4 per AlphaZero). The other 16 possibilities however do nothing but needlessly burn computer time. There is no doubt and it is 100% sure that none of them is any better than 1 e4 or 1 d4.

The best first heuristic was also used in solving Losing Chess: some lesser lines were added later.

#3031
"The more people question it, the surer you get."
++ It baffles me how you can question that. Are you a beginner who does not know that a piece down without any compensation loses the game?

I think I can honestly say I doubt if I'd win it as Black even against Stockfish. I'd put money on losing it against a 32 man tablebase if there were such a thing. 

Lasker used to say its a rook.  A rook down.  Not a piece.
There is considerable rationale in not including Ba6 in 'weakly' solutions.
But knocking out 1) a4 ... or any of the 20 white first moves at all - is just too intensely suspect.
But don't worry !   As I said - you've been getting control of the forum.
And for 3000 posts now !
Simply by refusing to cave in !   

#3034
"I think I can honestly say I doubt if I'd win it as Black even against Stockfish. I'd put money on losing it against a 32 man tablebase if there were such a thing. "

++ Yes, I guess that is true. However, we are not talking about practical play against Stockfish here with the inherent human errors, but rather about weakly solving chess. I.e. both entities commanding the white and the black pieces are presumed to play optimal moves.
Stockfish should win this against itself or against any present or future engine, or against the postulated 32-men table base. An ICCF grandmaster should win this against the postulated 32-men table base. In practice ICCF grandmasters resign when they lose a pawn without compensation. There is also no doubt at all that the postulated 32-men table base would list the entry 1 e4 e5 2 Ba6 as black checkmates in X moves, presumably with X < 50.

"Stockfish should win this against itself"

Heyyyy !!!   That's interesting !
What odds does a computer have to give itself ... to beat itself ??
A subject in itself !
But - tainted by Stockfish's pathetic findings of wins in obviously drawing situations.

#3035
"Lasker used to say its a rook."
++ Where did Lasker say that? A rook is enough to win, a piece is enough to win, a pawn is enough to win.
"The winning of a pawn among good players of even strength often means the winning of the game." - Capablanca
"An endgame with an extra pawn is won, the plan is to queen the pawn;
an endgame with an extra piece is won, the plan is to trade the piece for a pawn." - Capablanca

A pawn is Very Often not enough to win.
And a knight or bishop up often fails to win.
A rook is somewhat different.
Part of the theory of that is that if everything else is exchanged - the rook triumphs.  Its the Minimum Mating Material.
mmm  Rook up !!!

(could get a series of pingpong posts now where @tygxc actually knows what I'm talking about - but there's a kind of 'argument' about things we actually agree on.  Even though he's likely to maintain otherwise.
I think he does that all the time.   
But its okay)

Analogy:  You're walking through a particular part of town - and you walk by some busy tennis courts with many people playing ...
and you hear those volleys of Bop-bop-bop ... not quite like popcorn ...
has its own 'tennis' quality 

#3039
"A pawn is Very Often not enough to win."
++ Among weak players or if there is compensation yes, but generally a pawn is enough to win.
"A pawn is a pawn" - Fischer
One example is the King's Gambit 1 e4 e5 2 f4 exf4 3 Nf3.
"It loses by force" - Fischer
"I could not find a way for white to equalise" - Kramnik
This was confirmed by AlphaZero: see figure 4 (d) on page 10.
https://arxiv.org/pdf/2009.04374.pdf 

That is also the reason why most gambits have vanished from top grandmaster play.
Grandmasters go though a lot of trouble and accept all kinds of cramped positions just to win a pawn. Here is an example: Carlsen gambits a pawn and almost loses.
https://www.chessgames.com/perl/chessgame?gid=2122755 

In weakly solving chess I would not care to handle e.g. Danish Gambit.

Euler now mentioned by @Elroch.
Euler was a great Swiss mathematician.
His equation e to the (i x pi) = -1 has been considered by some to be the most beautiful equation in all of math.  
Its called 'Euler's identity'.
Unfortunately - I have no easy way to type the equation in proper algebraic format.  
e is the base of natural logarithms.
i is the square root of minus one and is the base of complex numbers - if I recall it right.  It was called j when I studied it back then.
pi is of course ...  a transcendental number like e but much better known to the public than 'e'.
Volume of pizza pie with thickness 'a' and radius z ...
Pi x rsquared x a = Pi x z x z x a.  Which algebraically can be written
'Pizza'.  

#3041
"There is a set of first moves that win, a set that draw and a set that lose"
++ Yes, that is true. The set of first white moves that win is conjectured to be empty. The set of white first moves that lose may be empty. That leaves all 20 first white moves in the same subset of moves that draw. However, by human logic per Capablanca no move accomplishes as much as 1 e4 or 1 d4. Thus if 1 e4 and 1 d4 are proven to be in the set of moves that draw, then as a corollary 1 a4 cannot be in the set that wins.
If 1 e4 and 1 d4 are proven not in the set of moves that win, then the logically inferior moves like 1 a4 are not in that set either and the set of winning first white moves is empty as conjectured.

#3041
"But note also that chess is not mathematics. "
++ Chess is a game, but game theory is a branch of mathematics and thus solving chess is mathematics.
Maybe the analogon of Capablanca vs. AlphaZero would be Euler vs. Appel & Haken.
Appel & Haken used a computer to prove the Four Color Theorem, that is not more reliable than the proofs of Euler without computer. When Appel & Haken finally had proven the Four Color Theorem (longtime known to be true, but not yet proven), many mathematicians doubted the validity of a computer proof.

Since you missed this, I will post it again.

To weakly solve chess, the game-theoretic value of the game and a strategy to achieve that value must be determined. Being 100% sure of something without proof means that thing is considered an axiom. Using axioms like "the game-theoretic value of the game is a draw" and "this strategy is superior over that other" to prove in fact the axioms themselves, is a fallacy known as "begging the question". Excluding "inferior" strategies makes actually impossible to falsify the assumption of their inferiority.

Many posts ago you said:

I asked if you can provide papers supporting this statement, because we use in general only two values of truth: true and false. Are you sure you did not mistake "provability" for "probability", reading something about fuzzy logic? If that statement was true, a proof could not be true at a higher degree, compared to a knowledge already 100% true.

That calculation is flawed for "begging the question" and other reasons, but you refuse to address its many problems.