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Comment by asimpletune | Hacker News Reader

I have to say it’s a completely inappropriate comparison to make since Stockfish was forbidden from using its opening book. I would like to see the results when both are at their best.

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The opening book was removed from Stockfish ages ago. Do you mean tablebases?

Another way of looking at it is that it would be inappropriate to give Stockfish an opening book but not AlphaZero, and I'm guessing the latter doesn't have one since that goes against its whole premise.

With that said, whether it's fair or not, I am curious to see how Stockfish with its opening book would compare to AlphaZero in its current state.

Edit: I just learned that things have changed quite a bit since I looked into computer chess more deeply, and Stockfish does actually not use a book. So they did play the default config. The below is thus completely off.

These engines are built for results, not as technical demonstrators. You are testing the engine in a scenario that it was not built to cover. Opening books are not optional add ons for these engines, they mean that the heuristics are not tuned for early game, and no work is put into optimizing the evaluation in that phase of the game.

If they could have beaten Stockfish in its default configuration (using book), they wouldn't have artificially weakened it, right?

I'm very curious as well, as there's no way the AlphaZero team hasn't scrimmaged against full-power Stockfish. It seems suspicious that they decided to go with a gimped version.

Just as another counterpoint to this, if you look at https://en.chessbase.com/post/the-future-is-here-alphazero-l..., they point out that there are a number of positions where AlphaZero definitively outplayed Stockfish in a non-opening position. There is definitely more going on there than Stockfish not having an opening book.

Stockfish doesn’t have an opening book. Chess engines are good enough now where they play sound openings without any need for direct human input.

It plays alright without a book, but far from its best. Deepmind say they chose StockFish 8 because it was the TCEC Champion. In the TCEC all engines are given an opening book + endgame tables. Further, since everybody gives chess engines these tools, engine writers usually don't optimize these aspects very much.

https://en.wikipedia.org/wiki/Top_Chess_Engine_Championship

Stockfish specifically dropped support for opening books since at least 2014, possibly earlier. The code base literally does not have the capability to use one any more. Regardless, in every game that I saw, Stockfish played perfectly sound openings that nobody would criticize it for.

Tablebases are a different story, but in every one of the games they released, where Stockfish lost, it was far behind by its own estimation well before tablebases would have had meaningful utility.

Neither opening books nor tablebases would have helped because Stockfish was handily losing the middlegames, not openings nor endgames.

Indeed. Most engines are pretty bad without their opening books. There was surprisingly little stress on this.

Actually, have you seen matches between SF without opening books vs SF with opening books? This isn't true anymore as far as I'm know.

Do you have any links to such matches?

Most engines don’t have opening books any more and haven’t for years.

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