"Tom E." wrote in message
...
Has the same game ever been played twice? (unintentionally)
I'm not talking
about scholars mates here, but something like 20-30 moves
past a 10 move main line opening of the French or something.
Tom

My guess would be "yes".

My reason for this is that although chess has an incredibly huge amount of
possible games, I think that the types of games being played fill a much
smaller subset (but still a huge amount in itself). For example, typical
games often involve typical openings. And after that, the set of legal
moves at each position is often narrowed down by commonly applied principles
(e.g put rooks on open files, etc.). Of course, we don't all think exactly
alike, but I guess there's a lot of commonality.

Combine this with the number of games of chess that have ever been played,
and I guess there's a fair chance of the exact same game being played twice.
Although, I don't think it will happen very often.

Finally, as someone else already mentioned, the question is rather vague and
open. Do we include correspondence games and games between computers!?

Gordon