(Context: I'm a very bad chess player, but have been getting into it lately.) I think we're fairly certain that chess players today would beat chess players of

(Context: I'm a very bad chess player, but have been getting into it lately.) I think we're fairly certain that chess players today would beat chess players of the past, in a regular 1 on 1 game. Assuming the old chess players didn't have time to prepare. Chess programs can rate the accuracy of moves, so we can see how accurate past players were. In addition, a lot has been discovered about more correct opening theory - a grandmaster of the past would make many mistakes in the opening that a modern grandmaster would be able to take advantage of, simply because they didn't know those lines.