>> She was called Leela Chess Zero — ’zero’ because she started knowing only the rules.
That's a common framing but it's wrong. Leela -and all its friends- have another piece of chess-specific knowledge that is indispensable to their performance: they have a representation of the game of chess -a game-world model- as a game tree, divided in plys: one ply for each player's turn. That game tree is what is searched by adversarial search algorithms, such as minimax or Monte Carlo Tree Search (MCTS; the choice of Leela, IIUC).
More precisely modelling a game as a game tree applies to many games, not just chess, but the specific brand of game tree used in chess engines applies to chess and similar, two-person, zero-sum, complete information board games. I do like my jargon! For other kinds of games, different models, and different search algorithms are needed, e.g. see Poker and Libratus [1].
The need for such a game tree, such a model of a game world, is currently impossible to go without, if the target is superior performance. The article mentions no-search algorithms and briefly touches upon their main limitation (i.e. "why?").
All that btw is my problem with the Bitter Lesson: it is conveniently selective with what it considers domain knowledge (i.e. a "model" in the sense of a theory). As others have noted, e.g. Rodney Brooks [2], Convolutional Neural Nets have dominated image classification thanks to the use of convolutional layers to establish positional invariance. That's a model of machine vision invented by a human, alright, just as a game-tree is a model of a game invented by a human, and everything else anyone has ever done in AI and machine learning is the same: a human comes up with a model, of a world, of an environment, of a domain, of a process, then a computer calculates using that model, and sometimes even outperforms humans (as in chess, Go, and friends) or at the very least achieves results that humans cannot match with hand-crafted solutions.
That is a lesson to learn (with all due respect to Rich Sutton). Human model + machine computation has solved every hard problem in AI in the last 80 years. And we have no idea how to do anything even slightly different.
That's a common framing but it's wrong. Leela -and all its friends- have another piece of chess-specific knowledge that is indispensable to their performance: they have a representation of the game of chess -a game-world model- as a game tree, divided in plys: one ply for each player's turn. That game tree is what is searched by adversarial search algorithms, such as minimax or Monte Carlo Tree Search (MCTS; the choice of Leela, IIUC).
More precisely modelling a game as a game tree applies to many games, not just chess, but the specific brand of game tree used in chess engines applies to chess and similar, two-person, zero-sum, complete information board games. I do like my jargon! For other kinds of games, different models, and different search algorithms are needed, e.g. see Poker and Libratus [1].
The need for such a game tree, such a model of a game world, is currently impossible to go without, if the target is superior performance. The article mentions no-search algorithms and briefly touches upon their main limitation (i.e. "why?").
All that btw is my problem with the Bitter Lesson: it is conveniently selective with what it considers domain knowledge (i.e. a "model" in the sense of a theory). As others have noted, e.g. Rodney Brooks [2], Convolutional Neural Nets have dominated image classification thanks to the use of convolutional layers to establish positional invariance. That's a model of machine vision invented by a human, alright, just as a game-tree is a model of a game invented by a human, and everything else anyone has ever done in AI and machine learning is the same: a human comes up with a model, of a world, of an environment, of a domain, of a process, then a computer calculates using that model, and sometimes even outperforms humans (as in chess, Go, and friends) or at the very least achieves results that humans cannot match with hand-crafted solutions.
That is a lesson to learn (with all due respect to Rich Sutton). Human model + machine computation has solved every hard problem in AI in the last 80 years. And we have no idea how to do anything even slightly different.
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[1] https://en.wikipedia.org/wiki/Libratus
[2] https://rodneybrooks.com/a-better-lesson/