A perfect game of chess is always a draw. Discuss.

More evidence that your arguments can be ignored.

The repetition rule is essential for competition. Without it, a drawn game or a game which both competotors wish to draw would never end.

Of course, it has absolutely zero relevance regarding whether chess is drawn by perfect play. Neither do 75 move rules or anything, since "perfect play" which is different from play producing a different result if governed by the 75 move rule clearly shows that the latter isn't perfect play. MAR's arguments are worthless.

@96

"All white attempts to win failed and all black attempts to draw succeeded (so they weren't even trying to win?)" ++ White has the advantage of the first move, called the initiative.
So if any side could win, then it would be white.

"Even if there were a pair of white & black mistakes in some game, there are backup plans to draw." ++ There are 97 different games, all draws, all perfect games. Let us assume some future ICCF grandmaster with some future supercomputer found a flaw in one game: black played a mistake that led to a lost position, but white made a later mistake that led back to the draw.
Even in that case other drawing moves for black are available from the other 96 games.
Even if the French were refuted, then the Najdorf, Petrov, open Ruy Lopez, Berlin are available as back-up to draw. Even if both the Nimzovich Indian and Grünfeld Indian were refuted, then the Queen's Gambit Declined, Accepted, or the Slav Defense are available as back-up to draw.

"if the starting position is a win it could be hundreds of moves"
++ No, because all the ICCF WC draws end in about 40 moves.

"chess (ICCF version) is a draw and the games are perfect under those rules."
++ 97 games, 97 draws. There used to be decisive games in previous years.
Each year reaped less decisive games. We have now reached perfection.

@103

"Try winning this against Syzygy with the 50 move rule in effect."
++ Completely irrelevant.
Chess is a draw without the 50-moves rule, so a fortiori chess is a draw with the 50-moves rule.

No. It's your big red telephone that's completely irrelevant.

@106

"the question of whether a version of chess is a theoretical win or draw is a mathematical one and shouldn't be confused with the results of practical play."
++ ICCF Correspondence chess is a scientific endeavour.
There is no clock ticking, no fatigue, no nerves.
Players have average 5 days per move and can use nearly everything available.
It is like what was done to weakly solve Checkers and Losing Chess: a human (here 2 humans) with computers. Each game represents 2 * 1.5 = 3 years of engine calculation. They often use several different engines on a position, or engines with differently tuned settings.

"most of the practical games are agreed draws in positions whose theoretical outcome is unknown" ++ This is a lie. Most of the ICCF WC Finals draws are 3-fold repetition or 7-men endgame table base draw. Some are agreed draws in positions where neither player had any hope to win. You cannot expect ICCF (grand)masters to play on in an opposite-colored bishop endgame that is known to draw.

Likewise, with present analytic means, it is impossible to PROVE any claim--that black wins, white wins, that it must be a draw--about the ultimate result of perfect chess games. Yes, it certainly seems that it should be a draw, but "our best-informed opinion" falls short of incontrovertible certainty.

All this was discussed in past threads. Since it's impossible to fully solve chess and we know that, it's therefore impossible to prove deductively that chess is a draw, by taking premises which we know to be true and manipulating them logically.

We can and do still know that chess is a draw with perfect play. A deductive proof isn't necessary and neither would it be reliable if it could be achieved, because it couldn't be checked.

It seems we just have different standards of "proof".

Not at all. I explained the differences and since a deductive proof is unavailable and will probably never be available and since we know that chess is a draw for reasons that are somewhat difficult to explain, my decision is to go with that. In my opinion we know chess is a draw. tygxc holds a similar opinion regarding that.

The inferential reasoning is that the game of chess starts off with a slight initiative to white, which some people consider to be worth about a fifth of a pawn to a third of a pawn, depending on the opening. It is considered that this slight initiative gradually lessens if both sides continue to play good moves, until at a particular stage in a game, the initiative has dwindled to nothing. It would take a inexplicable reversal of that trend to make a game won by one side or the other. There's no reason that there should be such a reversal, unless one side or the other blunders. Therefore it's drawn with best play and that is an inferential proof. There's no deductive proof possible. Consequently, that which I've just given is the best we have to go from.

I don't know if it's available in any books or theoretical papers anywhere, because I just put it together in my head: but it's correct.

@111

"Since it's impossible to fully solve chess and we know that, it's therefore impossible to prove deductively that chess is a draw" ++ No, it is not necessary to strongly solve a game to weakly solve it and it is not necessary to weakly solve a game to ultra-weakly solve it.

For all practical purpose Chess is ultra-weakly solved and the game-theoretical value of the initial position is a draw.

The ICCF WC Finals draws constitute almost a weak solution of Chess.
The strategy for the initial position to achieve the gametheoretic value of a draw against any opposition is to follow an ICCF WC Finals draw for as long as possible and then switch to an engine at 5 days/move until a 7-men endgame table base draw or a prior 3-fold repetition.

A strong solution of chess i.e. a 32-men table base of all 10^44 legal positions is beyond reach.

@112

"It seems we just have different standards of "proof"."
++ Here is proof by reductio ad absurdum.

Fact: 97 games all draws in the ICCF World Championship Finals,
by ICCF (grand)masters with engines.
10 exceeded the 50 days / 10 move time limit in otherwise drawn positions.

Hypothesis: chess is not a draw.
Then all 97 games must contain an odd number of errors (?).
An error (?) is a move that changes the game state from draw to loss or from won to drawn,
and a blunder (??) changes the game state from won to lost and counts as a double error.
So all 97 games would contain 1, 3, 5 ... errors and none would contain 0, 2, 4... errors.
It is absurd that some games would contain 1 or 3 errors and none would contain 2.
It is absurd that some games would contain 1 error and none would contain 0 or 2.
It is absurd that the ICCF (grand)masters and their engines would conspire to always make an odd number of errors and never ever an even number of errors.
The hypothesis was false.
Thus chess is a draw.

Q.E.D.

Hypothesis: chess is a draw and the 97 games are not perfect.
Thus all 97 games contain an even number of errors: 0, 2, 4...
It is absurd that games would contain 0, 2, 4 errors and none would contain 1 error.
It is absurd that the ICCF (grand)masters and their engines would conspire to always make an even number of errors and never ever an odd number of errors and never make 1 error.
Thus all 97 games must contain 0 errors.
The hypothesis was false.
Thus all 97 games are perfect games.

Q.E.D.

++ Similarly here is proof by absurdum..

Fact: 12 games all draws played under RCCF rules (FIDE competition rules but with the diagram in art 2.3 replaced with this one) in Arena by Rattigan on his computer.

Times per move ranged from 1s to 2048s (but this fact will nowhere be used, it's just thrown in for padding).

Hypothesis: chess is not a draw.
Then all 12 games must contain an odd number of errors (?).
An error (?) is a move that changes the game state from draw to loss or from won to drawn,
and a blunder (??) changes the game state from won to lost and counts as a double error.
So all 12 games would contain 1, 3, 5 ... errors and none would contain 0, 2, 4... errors.
It is absurd that some games would contain 1 or 3 errors and none would contain 2.
It is absurd that some games would contain 1 error and none would contain 0 or 2.
It is absurd that Rattigan and his engine would conspire to always make an odd number of errors and never ever an even number of errors.
The hypothesis was false.
Thus chess is a draw.

Q.E.D.

Hypothesis: chess is a draw and the 12 games are not perfect.
Thus all 12 games contain an even number of errors: 0, 2, 4...
It is absurd that games would contain 0, 2, 4 errors and none would contain 1 error.
It is absurd that Rattigan and his engine would conspire to always make an even number of errors and never ever an odd number of errors and never make 1 error.
Thus all 12 games must contain 0 errors.
The hypothesis was false.
Thus all 12 games are perfect games.

Q.E.D.

Fact: All 12 games contain blunders (Syzygy's theorem)

p∧¬p ⇒ q

Let p be "no games contain a blunder" and q be "@tygxc is a teapot"

p∧¬p

thus q

Thus @tygxc is a teapot.

Q.E.D.

5 days = 432,000 seconds >> 2048 seconds
MARattigan is an 800 rated player, no ICCF (grand)master
MARattigan lets his engine run without intervening as ICCF (grand)masters do, like letting a horse run without jockey
The position of MARattigan is a win and cannot be reached from the initial position by a perfect game of chess.

MARattigan is a teapot himself.

You failed to notice the comment "but this fact will nowhere be used, it's just thrown in for padding" - which applies also to everything you just mentioned.

And the position in question is the initial position under RCCF rules, which differ from FIDE rules by the change of one diagram compared with the many paragraphs of the ICCF rules. (Not that it's relevant, your argument would be discredited if it were a game of draughts. It nowhere uses any reference to the rules. Indeed your conclusion is that chess is a draw, not that ICCF chess is a draw.)

@119

"but this fact will nowhere be used, it's just thrown in for padding"
++ Of course the time per move and the engine speed are relevant.
You cannot draw valid conclusions from letting an engine blitz against itself.

If you are serious about your experiment, then take your 2048 second/move game,
then go forward until the error in respect to the 7-men endgame table base,
and for that move increase the time/move to 5 days. Is the error still there? Yes/no?

"the initial position under RCCF rules, which differ from FIDE rules"
++ Nobody but you is interested in RCCF rules, but in FIDE rules and/or ICCF rules.

"Indeed your conclusion is that chess is a draw, not that ICCF chess is a draw."
++ What is discussed here is 'A perfect game of chess is always a draw.'
A game of chess starts from the initial position per FIDE Laws of Chess 2.3.