Chess will never be solved, here's why

Actually I find Haiaku's (and Elroch's) reasoning to be quite sound, ergo my willingness to take a break from refuting the same old stuff yet again.  It's better coming from new quarters.

You cannot proceed with Tygxc's plan and achieve a valid solution of chess, or even a single ECO code for that matter .  This is because his definition of weakly solved is flawed and contains numerous interdependent assumptions layered on to allow for knocking 10^44 down to 10^17.  Relying on Stockfish for perfect evaluations to bridge to the actually perfect evaluations of tablebases being number one among them.  Removing all promotions, then adding back in "acceptable" promotions without actually evaluating what that even means.  Casting aside dozens of orders of magnitude for "nonsensical" positions (also an assumption) based on sampling a small set set of positions, when if even 1 out of a million of the positions sampled are valid positions, that limits your reduction to 6 orders of magnitude. Assuming Sveshnikov knew anything about solving chess vs. just analyzing openings when there's no demonstration that his statement is anything more than an offhand boast at a dinner party.

If Tygxc had the money and achieved his 5 year analysis goal, he would be able to produce an engine that plays exceptionally well, perhaps...but it would not be a solution for chess at all.

That doesn't mean you need a strong solution to weakly solve chess.  You can weakly solve chess with brute force even without any further pruning...just not within our lifetimes by any foreseeable technology.

"But don't you see that this definition is redundant? If both players don't make mistakes, how could they make moves with a better outcome?"
++ Yes, it is redundant indeed. The word 'ideal' could be striken as the 'optimal' implies the same.

"it seems that all posters here have difficulties communicating with you"
++ They seem unable or unwilling to understand concepts.

'One asks: "what do you mean by that?"'
++ Whenever somebody asks that I explain patiently, sometimes repeating or rewording what I have written 100 posts ago.

"And this behavior is restricted only to this "5 years to solve chess" topic, for apparently no reason; you do not behave like this in other threads with different topics."
++ I get more adversity and insults here probably because people emotionally do not want chess to be solved any time and thus attack me for my opinion of the contrary. I get insulted and ridiculed and I have always stayed polite. Maybe on pure chess related issues the lower rated are not that outspoken.

"You said that you will hold to your position until others will prove you wrong"
++ That is right, I wellcome any other views supported by evidence

"but none has understood what kind of proof you would accept"
++ I accept any argument based on facts and figures. None has cared to provide any facts or figures. They just say I am wrong, a crackpot, .... and then state their own unfounded opinion as a fact without any evidence at all.

"Provability is a higher degree of truth.
What is this, fuzzy logic? Formal logic uses only two discrete value of truth: true and false."
++ It is actually a quote from a Scientific American article on unsolved issues.

"Maybe they thought them true, but as @Elroch said, the vast majority of scientists refrain to say they know they are true, do you agree?"
++ Some work on proving the Riemann Hypothesis, non on disproving it. The same was the case with Fermat's Last Theorem and the Four Color Theorem and other. Formally it is 'hypothesis' or 'conjecture'.

"In fact, they are not proven, that's why we still call them "theories"."
++ That is no longer the case: people used to call it Relativity Theory and Quantum Theory, but nowadays it is just Relativity and Quantum Mechanics / Electrodynamics / Chromodynamics.

"If scientists know that a theory is true, how could they abandon it, if falsified (as it happened to Galilean relativity an classical mechanics)?"
++ Galilean Relativity and Classical Mechanics are still considered true in appropriate areas: speeds much lower than the velocity of light, wavelengths much smaller than the De Broglie wavelength etc. Buildings and machines are still designed by classical mechanics. Synchrotrons are designed using relativity. Semiconductors are designed using quantum mechanics.

"If we solve chess in 5 years, then it is proven it is feasible"
++ True. It is worthwhile to discuss the feasibility.

"our knowledge of the universe is incomplete, so tomorrow we could discover a new phenomenon, which contradicts relativity for example, as electromagnetism led physicists to abandon Galilean relativity." ++ True.

No need to say that. They simply play the best moves, right?
++ It is not that simple. It is not clear if 1 e4 is any better than 1 d4, but it is clear that both are better than 1 a4 or 1 Nh3.

"If a candidate ideal game leads to a draw, then only white moves need retracting.
Why? Isn't it an ideal game?"
++ a candidate ideal game only becomes an ideal game after it is proven that its moves are indeed optimal

"You earlier agreed with me that to solve chess that would not be enough, right?"
++ To solve chess needs calculation towards the table base, but logic can be used to guide i.e. prioritise the search.

"Being 1 pawn up is enough to win.
You cited A0. It doesn't consider the game won in this case, it depends on positions. It's a good advantage, though (expected score about 0.75 according to evaluation functions of strong engines)." ++ "1 pawn wins" - Capablanca

"I respect your opinion even if we disagree." ++ OK let us agree to disagree.

"If chess is a win for Black, with optimal moves, it's a win for Black. Period. Agree?"
++ Agree, but that is not the point. If chess were a win for black, then white's most resistance would be to try and lose a tempo. Say 1 e4 e5 is a win for black. Then 1 e3 e5 2 e4 is a win for white. Then 1 e3 e6 2 e4 e5 is a win for black.

'Right, statistically, but we have to calculate to prove it is always the case, correct (you say that!)' ++ Right: we have to calculate.

@Optimissed:

A game is called strongly solved if the best move can be found from every position in the game. To solve chess weakly that is not necessary. Think about a middlegame position with a big advantage for one colour: you can win that game in many ways. An engine set to give you an evaluation in WDL might easily give you 1000 (w=100%) for almost any move you play. If you just find one of this equivalent moves every turn against any opponent's move until a tbh, you have weakly solved the game from that position, while to solve it strongly you should find the best move for all the child nodes of that position. So in a strict sense no, you don't have to solve the game strongly to solve it weakly. In practice there could be not much difference, idk, but for sure to solve chess strongly would be more demanding. A "semi-strong" solution is not defined.

Maybe not 'oblivious'.   More like 'loyal to his client'.
Participants in discussion often pick a side.
Objectivity and centrism and 'issue before preconception' are often seen as 'fence-sitting'.
They're seen that way.  Perception.   Valid perception ?
Usually not valid.  In love and war and in courtrooms - may be different.

His perception that he must defend his side - well he decides on that for himself.
But then there's perception of the perception.  The bigger picture.
That's where 'gestalt' could come in.  
Experience:  when behaviours/cognitions are discussed - the behaviours/cognitions then happen or continue - instead of the discussions of same.

Regarding the semantics of 'weak solving versus strong solving' -
that hasn't gone anywhere in over 1000 posts.
Some want it to be A or B. 
Others recognize the realities of many grey areas between the extremes.
But its a small aspect and mostly a red herring.  
If only because weak versus strong would be what whoever wants it to be.

There isn't any point in "strongly solving", because most logically possible positions are nonsense positions: the results of random moves or gross blunders. It doesn't help our knowledge of chess in any useful way, so that isn't part of a useful solution of chess.

If you had read my posts, you would have understood my argument: but unfortunately, you haven't. It is you and others who should consider and think carefully about the process of so-called weakly solving. How are optimum moves for each position found? Think about it. Without an almost magically powerful algorithm which can recognise the essence of positions at a glance (if we had that, we could just flash it at the start position, after all) it's necessary to do a semi-strong search *around* the areas where optimum moves may be found, and even that's quite presumptive. So in practice you cannot do a weak solution except by doing a semi-strong solution.

I have the impression that no-one here, with the possible exception, strangely, of playerafar, and none of the theorists, so far as I can see, have understood that. [Certainly not Shveshnikov and tygxc ] And that's why I called that set of definitions "hypothetical" or "spoof" definitions. They are of no practical value because they consist of bland instructions to "produce an algorithm that .... etc" 

A "semi-strong" solution is not defined.>>

Of course not and that's a very strong indication that the theorists don't know what they're talking about. If that seems a bit strong, what am I supposed to think? That they're right and I'm wrong, even though their ideas don't take into account HOW solutions can be found?

If you need to add "1/4 cup salt" to your homemade ice cream recipe for it to taste good, does it matter *how* you measured the 1/4 cup of salt?  Does it matter if one method of measuring the salt was more robust, convoluted, or difficult than the other?  Does it matter whether you milked the cow yourself or bought cream at the store?  Does it matter whether you stirred clockwise or counterclockwise?  No.  It doesn't.  The recipe stands anyway and the results stand anyway, and either fit the criteria of what the recipe called for, or not.

The methods used to obtain the solutions have zero impact on whether a game is weakly or strongly solved.  There's no need to keep getting tied down to the words "strong" and "weak" and assuming they refer to ease of obtaining the result.  They simply mean whether the solution works from just one position, or any position.  

You can argue that a weak solution is only marginally more difficult to produce than the strong solution for a given game, and thus claim that the strong solution makes more sense to go after...but that still doesn't make them the same.

Regarding the 236,196 'material situations' in chess -
I think its in order to take a look at one of them.
A particular one.  After a little more analysis.

Nobody in the forum seems to think chess can be truly solved.
But part of the forum topic says 'here's why'
and that makes more sense.  Discussing the 'here's why'.
And there has been some of that.

You'd do a lot better by understanding the problem and understanding my explanation than making ice cream with salt in it.

You'd do better by realizing I know exactly what I am talking about, and while you're at it, you might read up on why you add salt to ice cream ...

https://www.scientificamerican.com/article/scrumptious-science-making-ice-cream-in-a-bag/#:~:text=Why%20is%20this%3F,is%20called%20the%20freezing%20point.

<<The methods used to obtain the solutions have zero impact on whether a game is weakly or strongly solved.  There's no need to keep getting tied down to the words "strong" and "weak" and assuming they refer to ease of obtaining the result.  They simply mean whether the solution works from just one position, or any position.>>

You see, without a methodology, there's no weak solution and any methodology for a weak solution has to refer to a semi-strong solution. There's no alternative, because it has to be understood why moves are optimum. After all, it asks for proof.

Without knowing how to make it, there's no ice-cream or maybe there's salt in it.

Consider trying to find a weak solution for position x. The solution consists of optimum moves for both sides. So we have to consider a branching tree which starts at x and follows all reasonable looking moves for both sides and some pretty unreasonable ones too, because that's where the surprise could be. And that's what I mean by a semi-strong solution. Starting at position x and discounting random moves and gross blunders which obviously lose. Then, gradually, the semi-strong solution is pared down until it ultimately becomes the weak solution. So the weak solution is unattainable without the semi-strong solution. It beats me why these so-called theorists don't make a thing of the semi-strong solutions. There are two possibilities. I'm stupid or they're incompetent. I'm not stupid.

There's no such thing as a semi-strong solution in game solving.  If you achieve a solution from multiple positions but cannot produce one from *all* positions, then you have achieved only individual weak solutions for each position.

The solutions themselves can exist with or without *any* methodology.  In a brute force weak solution for chess, you would not be able to "understand why the moves are optimum" in a discrete sense, you would simply have exhaustively eliminated all other possibilities, leaving the solution at "optimum" but without being to articulate exactly why each move along the way is the best move. Hopefully we all know the applicable Sherlock Holmes adage...

Indeed, the definition on Wikipedia gives that "how", and that's why I don't like it: it mixes up the "what" and the "how" in a way that, imho, can be confusing/misleading. Take B(lack) and W(hite): if B is an engine, which searches at every turn for the best (according to its evaluation function) reply against all the possible moves by W, and at least B draws, you have weakly solved the game because:

1) If B wins, W cannot win or draw (because at every turn all legal W moves are checked and replied)

2) If B draws, W cannot win (because at every turn all legal W moves are checked and replied)

In either cases, we have found the game-theoretic value of the game and a strategy (i.e. the sequences of moves against all the possible moves by W). If B loses, we cannot say anything, because the algorithm the engines uses could be too weak to draw or win in a reasoneable time. In fact, @Elroch correctly mentioned that the definition usually includes a part (that I didn't include to avoid possible furhter confusion imo): "under reasonable resources". It's clear that we cannot leave an engine calculate 100 years on every move, so the engine has to be strong enough for the task to be completed before the end of the world.

This also applies to "understanding" a brute force solution.  If all 10^44 positions were exhaustively evaluated, then in theory you could have the "engine" with the solution print out or read out an explanation of *why* each move was optimum, by telling you every single move that was *not* optimum, and exactly why that sub-optimal move ended being worse than the optimal move later on...but generating that explanation and reading it back would probably take more resources than the solution itself, drone on for billions of billions of years, and be utterly incomprehensible to any human being listening to it after the first 3 minutes in.

There's no "how", if a weak solution demands a semi-strong solution plus algorithm and the semi-strong solution is banned, as seems to be the case. Then there's no way to find any solution, so any discussion of a definition of a weak solution becaomes nonsense. How do you define something that cannot exist?

Well, putting your assumption about your first sentence being correct aside ...humanity defines things that cannot logically exist all the time in many branches of science and mathematics.

Particular situation of the almost quarter-million material situations in chess:  (much much more than a quarter-mill if you factor in promotion of pawns too)
In the particular example each side would have one of each possible piece.  K-Q-R-B-N-P.  
Is it 'easy' to count up the possible positions for that one before 'solving' for illegality versus checkmate versus 'unsolved for now'?  (which computers could attempt)
Yes.  I'll do that right now.

To get precision - the hardest part appears to be reconciling pawns with bishops.
Exactly how many possible positions of those two piece types depends on what color squares the bishops are moving on.  The two pawns could take none of their 48 squares from the bishops - or one - or two.
Sooo .... advisable - just let the computer take care of any illegalities.
And I'll make it that the bishop for each side is a darksquare bishop.
And that the pawns can't take a square from them - if they can - the computer will reject it as illegal.  (yes - that's why its to be programmed that way).   That's part of the 'Solving'.  Progress.

Position count:
32 x 31  (bishop placements)
times  
48 x 47  (placements of the two pawns)
times
60 x 59  (places for the two Kings to be - in each of the cases for the pawns/bishops - does allow for 64 spots for each King)
times
58 x 57  (the Queens)
times 
56 x 55  (rooks)
times
54 x 53 (knights)

Total:
32x31 x48x47 x60x59 x58x57 x56x55 x54x53

which is:   2.3 x 10 ∧ 20th power.
In other words about 2 times  100 million trillion positions.  
Be generous and say a present-day supercomputer can work at 1000 petaflops.  (1000 trillion operations per second)  
That would mean it could put in just one 'operation' on each position - in 200 thousand seconds.   Which is well under three days.
But just one op on a position would do hardly anything.
How many ops does it take to 'solve' one position?
Could a computer even define a position - with say one meg?
or simplifying - make it a base 10 million instead of a binary 'meg'.
To 'solve' a position - is going to take a lot more 'ops'.  
Many other positions would have to be considered.
Say you could 'define' in a million ops and 'solve' in a trillion ops.
That's very very generous.  

Then you're going to need over two trillion days.
But that's just for that one 'material situation'.
Now multiply by a quarter million for all situations.
You'll need over half a million trillion days.
About a trillion years.
Want to have the supercomputer 'solve' a position with just a billion ops?
Then its a billion years.
Have it 'solve' a position in a measly million 'ops'?
That's still would take a million years.  To 'solve' chess.
An 'op' is like the computer using machine language to add two base two numbers -   like add 32 to 2 or whatever.
An 'op' is infinitesmal ...

There's some of the 'here's why' folks.  
A million years to 'solve' chess would be wildly optimistic.
If computer systems/software/programming could run 1000 times faster -
then 1000 years would still be a crass under-estimate.
Because its going to take more than a million ops to 'solve' an individual positon.   Much much more !   

I'm not surprised that this argument is rumbling on and on and on. Can I give a hint? Forget all about what the experts say and use your own resources. Then, you'll begin to define first principles and think originally. See if you come up with what the experts say.

I would say that this has every indication of being a situation where the experts DON'T understand it and are just, sort of, weakly agreeing with each other. That's because, if they were really thinking for themselves, there would be strong disagreement, within their ranks. If there actually is strong disagreement, that's healthy. No disagreement = very unhealthy and not to be trusted.