How many moves?

Master of the drunker art of chess, nice

Just out of a morbid curiosity, without the 50 move rule, could a chess game go on forever? Let's have the threefold repetition rule apply to make this "forever" game more of a challenge. 

I do understand that sufficient material must be on the board for the game to still continue, but would the material eventually go poof? 

The material would need to withstand all manner of abuses, especially when tempers run hot.

Has anyone been killed by a chess piece?

@ woodshover. This is deep stuff. Excellent post.

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Computers must have had extremely long games against each other. Does anyone know the greatest number of moves played by two computers? 100? 1000? One google?

Now, I've heard of the art of drunken boxing, chess boxing, and even drunken chess, but do you suppose there's a market for drunken chess boxing?

Even with the 50 move rule (and three-fold-repetition) a game could technically go on forever.  Neither obligates a draw be declared -- they merely provide for the right to claim one should the situation arise.  If neither player claims, play continues.

How did you find this out? I don't have Facebook

assuming people do claim the draw, then with 3-fold-repetition it would end.  it would be about 2 times the total number of possible positions cuz after each position has been visited twice the 3rd time it would be a draw.  this is some insanely large number so technically it can't last forever, but it could never be played out anywhere near the end

I mostly just want to know where this river of gin is and whether it by chance flows into an ocean of tonic.

Are you sure? Wouldn't all the remaining pawns eventually go on to glory, promoted to some other piece, then get gobbled up, leaving only two kings on the board?  Pawns can't go backwards.

Now this would be interesting.

Sure, but pawns aren't the only pieces.  K+N+N vs K+N+N isn't a draw due to insufficient material, so play goes on....

Remember that week you spent in Riverdale, IL, May 1998?  No?  I'm not surprised.  But the locals do, and I have a friend who lives there...

That's what I meant by promotion, since pawns can't move backwards. Some pawns could promote to knights.

But wouldn't the knights eventually get captured, thus leading to insufficient material?

Does this matter in real life?  Nope. Again, it was a simple curiosity raised by the OP.

Yes, as far as I can tell it would have to end, assuming that one of the players claims a draw as soon as it is valid under three-move repetition. The length of the game would be insanely massive though, considering that it would probably start like this: Without moving the pawns, have both sides permute all possible positions by moving just their knights. Then do so one more time if possible, because a second repetition doesn't hit the three-move repetition yet (though this may not be possible given that I'm not sure whether you may already have to repeat some positions in the process of getting the knights into new positions). Then repeat these positions again, but now with all possible permutations of the rooks (because b1, b8, g1 and f8 have been freed up when the knights moved out). Then you move one pawn...and my mind is already boggling at how many moves we've made. But yes, at some point pieces will have to be captured, pawns will have to be promoted, and eventually the game will end. The number of moves would be insanely high though, probably in the order of magnitude of the Shannon number (because in effect we are trying to achieve every legal position in chess. Twice, in fact, but 1) that doesn't affect the order of magnitude and 2) I'm not sure if it's possible to reach some positions without repeating previous positions, so we can probably dock off some anomalous positions like that).

Of course, but that would be kinda trivial.

If you assume that a draw will be claimed as soon as it is possible (after all, it would be by definition the best move for at least one of the two players) then yes, 5870.5-5950 is the answer.

I'd done some calculations of my own some time back and similar to ozzie, believe I came in somewhere in between the two figures and posted the method and results in a different blog post by kurtgodden that's since disappeared.  I can't remember the exact number however.

pity I can't sort my chess.com games by moves :(

Yeah, more options to juggle around the game archives would be fun.