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Isaac King's avatar

I appreciate you writing this article! I've been wondering what your thoughts are on AI risk ever since you started the blog.

As some background, I first encountered you on Full Stack Economics, and when you announced this blog I subscribed here as well. Thus far I've found it very well-written and informative. In particular I loved your deep dives into self-driving technology, and found them very useful for forming my own opinions in that arena. You're one of my primary sources for news on contemporary AI developments, and I really appreciate the blog.

With that context, I want to say that I found this article to be very disappointing. It barely engages with the arguments in favor of AI risk, either handwaving them away without justification or omitting them entirely. Several sections even contain relatively simple mathematical errors that have nothing to do with AI in particular.

I'm writing up this comment because I believe AI to be by far the most impactful technology on the horizon, and it's vital that we can make good predictions on its impacts. If AI is indeed a threat to humanity, that would eclipse the importance of nearly every other issue humanity faces, and would justify strong measures to prevent it. And if AI is *not* such a threat, it has the potential to end poverty and war, saving millions of lives. In the latter case, we have a responsibility to develop it as quickly as possible. Figuring out which prediction is correct is *really important*.

To address things one at a time:

Chess:

You say that people have been mislead by chess, because chess follows simple deterministic rules and can therefore be solved by algorithms, which doesn't apply to the real world. This is a category error; there's no sharp delineation between those two domains. The real-world, just like chess, follows a set of relatively simple deterministic rules called "physics". Each "move" leads to a known outcome, which can be brute-force searched.

The difference, of course, is that the real-world game tree is vastly larger. The average move in a game of chess has about 35 options, compared to the number of particles in the observable universe is about 10^80. However this is less relevant than you might think, since chess's game tree is *already* large enough to be intractable to brute-force searches deeper than just a few moves as in your computer science class. Chess-playing algorithms succeeded by doing aggressive tree-pruning to get the search space down to a manageable size, along with heuristic arguments hardcoded in by human experience.

The piece valuation you used in your program is exactly such a fuzzy heuristic; nothing in the rules of chess assigns a value of "5" to a rook, and the actual usefullness of a rook varies wildly based on the exact position. Humans played thousands of games of chess, learned via trial and error and intuition how useful each piece was relative to each other piece, and then hardcoded that into their computers. A chess-playing algorithm like yours is *already* doing exactly the sort of knowledge-based heuristic approach that you claim computers aren't good at.

Early chess-playing pioneers like Deep Blue did rely on humans to explicitly program in those heuristics; they weren't doing the foundational reasoning themselves. But that changed in 2017 with AlphaZero, which learns chess entirely from scratch via neural network. It trained by playing chess against itself for only 9 hours and was then pitted agains the best human-coded chess-playing program, StockFish. AlphaZero won 25 games to 3.

The sort of pure algorithmic approach to games that you describe can only be used on very simple games like tic-tac-toe, and most of the things that computers have recently started doing much better than humans at use fuzzy heuristics learned by trial and error, just like humans do. AlphaStar, for example, is a neural network that can play Starcraft better than almost all humans. (Starcraft has a vastly larger game tree than chess, being more akin to the real world in the precision with which different actions can differ, and is also a hidden-information game where the players have to reason probabilistically about what the opponents have access to or may do.) OpenAI Five does the same with Dota 2. And outside of video games, DALL-E has far surpassed human artists in generality and visual beauty and fidelity. (It's still very poor at understanding an English description and converting that to a conceptually corresponding image, but that's a different skill.)

Your understanding of the real world also seems quite simplistic in certain domains. You say "The simplicity and predictability of chess allow computers to “look ahead” and anticipate the likely consequences of any potential move. Most real-world problems are not like that." and talk about military planning as an example of this; much of military strategy is doing exactly what you claim they don't do! The field of mathematical game theory was developed largely as a way to predict the actions of other nation-states in response to possible decisions, just like one does in chess. As you point out, real-world planning is a partial information game rather than a perfect-information game like chess, but that doesn't really have anything to do with the ability to plan ahead. Planning ahead in a hidden-information game looks very much the same as in chess, except that you ascribe probabilities to each of your opponent's moves and calculate the move you can take with the highest expected value.

There's a reason why game theory and wargaming both have "game" in their names; there's no sharp delineation between "game" and "geopolitics"; they're both complicated systems of rules, agents, incentives, and payoffs. Geopolitics is the same kind of thing as board games, just a more complicated instance.

Knowledge vs. computation:

If I understand your argument correctly, it's that general artificial intelligence will require more training data than humans currently have available to give it, and that much of the data we do have is redundant.

I think you actually understate part of this argument. The first important question is whether neural networks are capable of general intelligence *at all*. Our understanding of the human brain is extremely poor, and while neural networks are similar to them in many ways, they're also different in many ways. It's entirely possible that no amount of training data could ever get a neural network to human-level intelligence. (For more on this I'd highly recommend the debate between Scott Alexander and Gary Marcus: https://www.astralcodexten.com/p/somewhat-contra-marcus-on-ai-scaling)

But assuming that neural networks are capable in theory of general intelligence, it seems unjustified to point to limited training data as a relevant constraint.

* You point to a paper that estimates we'll run out of training data by 2026. This may be true, but what about the ~2.5 years before that happens? We've already seen dramatic improvement from GPT-2 to GPT-4, and if there is some point at which the amount of training data becomes "enough", you haven't provided any estimate of where exactly that point is, and it's entirely possible that it's above GPT-4 but below the total amount of data we have to throw at GPT-5.

* Humans are generating data at a frantic rate that's only increasing as the internet plays a larger and larger part of our lives. We may "run out" of unused training data in 2026, but that would only limit growth in training dataset size to the amount of data that humanity produces in a year, which is... a lot. Even if the amount of data needed for GAI is above the 2026 threshold, we'll still get there eventually, potentially only a few years later.

* You focus on human-created data, such as English passages. This is presumably because current leading AI models are language models, which is because that's what people want. AIs that can predict human language would be very useful to humanity, so that's where most of the funding goes. But when we're talking about *general* intelligence, capable of reasoning about the world from first principles and learning in much the same way that a human baby does, why would it need to be training on human language to start out with? There's nothing fundamentally special about humans, we're just a particularly complicated part of physics. The Large Hadron Collider produces more than 1 petabyte of data *per day*. The Event Horizon Telescope collected 5.5 petabytes of data in April of 2018. What happens when someone pipes all of that into a massive AI model? Nobody's done it yet because anything short of general intelligence will be unhelpful to the physics community, so the funding just isn't there. But if the rapid pace of increasing interest in AI continues, someone will do it eventually, and an AI capable of predicting physics is also capable of predicting human behavior as a side effect, since humans run on physics.

(Continued in a reply, I ran into the comment length limit.)

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Andrew Whitby's avatar

I'm sympathetic to the overall argument, but if one person could reach the frontiers of (written) knowledge in every field at the same time, they could probably come up with a lot of novel ideas. Actual academic disciplines remain very siloed, useful human lifespans are pretty short if you consider it takes maybe 10 years to reach the frontier of a PhD-narrow field, and the incentives are very much against reaching that frontier in (superficially) unrelated disciplines.

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