Stuart Russell

And human professionals are sitting there for five, 10 minutes deciding what to do and AlphaGo in less than a second can instantly intuit what is the right move to make based on its ability to evaluate positions.

And that is remarkable because, you know, we don't have that level of intuition about Go.

We actually have to think about the situation.

So anyway, that capability that AlphaGo has is one big part of why it beats humans.

The other big part is that it's able to look ahead 40, 50, 60 moves into the future.

And, you know, if it was considering all possibilities, 40 or 50 or 60 moves into the future, that would be, you know, 10 to the 200 range.

So way, way more than, you know, atoms in the universe and so on.

So it's very, very selective about what it looks at.

So let me try to give you an intuition about how you decide what to think about.

It's a combination of two things.

One is how promising it is, right?

So if you're already convinced that a move is terrible, there's no point spending a lot more time convincing yourself that it's terrible because it's probably not going to change your mind.

So the real reason you think is because there's some possibility of changing your mind about what to do.

Right.

And it's that changing of mind that would result then in a better final action in the real world.

So that's the purpose of thinking is to improve the final action in the real world.

And so if you think about a move that is guaranteed to be terrible, you can convince yourself it's terrible.

You're still not going to change your mind.

Right.

Right.