It's clear to me that humans are at a loss when it comes down to playing against computers. (not only due to the answers to my last question (Humans against computers).

But, would humans (maybe a team of us) have a better chance of winning if we have a longer time per move or a shorter time?

2 Answers 2


Longer time lets both sides to calculate the variants deeper.

In blitz games (< 5 min) computers are terribly strong and we have no chance. Computer's reaction is too fast and it can compute lots of variants in early few seconds. On the other hand humans are potential to make blunders.

In games with 15-60 minutes engines are strong too, but humans have chances to avoid overlooks, obvious mistakes and they can analyze the position better, but yet it's hard to resist against engines.

In long games, engines can discover more variants, the problem is by processing deep variants the state space tree gets huge and finishing depth N and getting into depth N+1 consumes too long time. In other words, if an engine makes its decision after 4 hours thinking on a position, it's rare for it to change its decision to another move by more 1 hour thinking.

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On the other hand humans have more time to analyze positions strategically (the only thing that humans are still better than engines. At least it's comparable to engines)

So my answer is long games can give us a better chance to play better against computers.

  • 1
    +1. yes.. I realized that when play with my brother.. engine will trap in unnecessary branch at longer time, in other hand, human can easily jump into more valuable branch. In this state, chess engine still has leak on evaluation value and selective decision since it has benefit in computing value. Oct 19, 2013 at 10:42
  • How long does the game need to be before humans have the edge over computers? Are humans still better than engines when it comes to correspondence chess?
    – kuzzooroo
    Mar 24, 2014 at 3:19
  • In answer to my own comment: this answer says that humans are still better at correspondence chess.
    – kuzzooroo
    Mar 25, 2014 at 0:57

As human beings, we can't calculate as fast as a computer. In fact, there are many things which human beings can't do as fast as a computer, including numerical calculations. Hence, for a match to be considered 'fair', human beings should be given adequate time for thinking. This would assist them in faring better against the computer. Today, machines appear to have surpassed humans and the match where Deep Blue defeated Kasparov created history of a kind. For humans, apart from calculation, intuition, instinct, and experience also matter. However, I don't think we should be dissapointed with the fact that machines can defeat grandmasters. The reason they are able to do so is because apart from calculation, they are also fed with opening book data and various other data and strategies which grandmasters have learnt only by experience. This knowledge which is fed into the engine is knowledge which human beings have acquired over hundreds of years so ultimately, the credit for their success also goes to the human beings who have accumulated this wealth of knowledge over the years.

Mathematically speaking, for eg. if you consider the starting position, there are 20 possible moves. After 1) e4 .. e4, this increases the no. of possible moves to 28. Mathematically speaking, the algorithms used by computers are of exponential complexity - meaning that if you consider a number,for eg., 28 as the average no. of possible moves per person - so if a computer needs to calculate to a depth of n, it would have to consider 28^n possibilities. Such exponential complexity algorithms are amongst the most difficult algorithms for a computer to handle. To get an idea of this, 28^5 = 17 million(eight digits), 28^10 = a 15 digit number. By contrast, 8^5 = 32,000, and 8^10 = 1 billion(10 digits). If there are lesser pieces on the board, the computer has fewer moves to calculate. However, fewer pawns would mean more openness which means more moves to calculate. So if you want to beat the computer, you need to keep as many pieces on the board as possible(avoid exchanges) - go for a slow game with no exchanges near the beginning, where the computer still has a lot of moves to calculate even after it goes out of the opening book.

  • +1. good opinion sir. even my Houdini will slowly become 'fool' when played with defensive player.. ^^ Oct 20, 2013 at 11:22

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