How Computers Have Impacted Modern Chess

Old school chess preparation involved a deep understanding of the knowledge/techniques presented in classic chess books written by the sport's greatest players, intensive studying of the biannual Chess Informants and an awareness of the new ideas published in various chess periodicals. In The Cyber-Renaissance in Chess, David Goodman and Christopher Chabris argue that powerful chess playing engines and multimillion game databases have transformed chess and elevated the quality of play:

Once laptops could routinely dispatch grandmasters, however, it became possible to integrate their analysis fully into other aspects of the game. Commentators at major tournaments now consult computers to check their judgment. Online, fans get excited when their own "engines" discover moves the players miss. And elite grandmasters use computers to test their opening plans and generate new ideas. 

This wouldn't be very interesting if computers, with their ability to calculate millions of moves per second, were just correcting human blunders. But they are doing much more than that. When engines suggest surprising moves, or arrangements of pieces that look "ugly" to human sensibilities, they are often seeing more deeply into the game than their users. They are not perfect; sometimes long-term strategy still eludes them. But players have learned from computers that some kinds of chess positions are playable, or even advantageous, even though they might violate general principles. Having seen how machines go about attacking and especially defending, humans have become emboldened to try the same ideas. 

Goodman and Chabris note that the rise of chess computers has been accompanied by a tremendous increase in both the number of Grandmasters in the world and the number of Grandmasters who have ratings of at least 2700:
 
When the first international rating list was published in 1971, the only player rated over 2,700 was Bobby Fischer. (In chess ratings, a 100-point advantage corresponds to an almost two-thirds chance of winning a match.) Fischer went on to beat Boris Spassky in their celebrated 1972 world championship match. In 1974 there were two players with 2,700 ratings: Fischer and his successor Anatoly Karpov. Even by 1997 there were just eight.

There are currently 50 players who sport 2700-plus ratings and Magnus Carlsen--who just won the World Chess Championship--has the highest rating of all-time, 2872. Computer analysis suggests that Carlsen and today's other elite grandmasters play more accurately than the grandmasters of previous eras did. Carlsen has been dubbed "the hero of the computer era" and his moves tend to mirror the top choices of the best computers even more than the moves of his chief rivals.

Does this mean that Carlsen is the greatest player of all-time and that he is lording over the toughest group of grandmasters in chess history? Not necessarily--while Carlsen's rating is higher than the best rating achieved by Bobby Fischer, Fischer was much further ahead of his contemporaries than Carlsen is: Carlsen's rating is 69 points higher than the rating of the number two player (Levon Aronian) but Fischer's July 1972 rating (2785, which stood as the record for 18 years) was 125 points higher than the rating of the number two player (Spassky). Fischer stood head and shoulders above even his greatest rivals and it is reasonable to assume that, given the opportunity to train with modern computers, Fischer's talent and work ethic would have similarly lifted him above today's players as well.

Such speculation does not in any way diminish the significance of Carlsen's accomplishments; Carlsen appears to possess better emotional/psychological balance than Fischer did, so Carlsen's talent, charisma and energy combined with the technological advances that enable average players to closely follow grandmaster games could help chess become more of a mainstream sport than it has ever been.