[chongli]

Right. But how do you define it intensionally? Saying that "humans have a lot of it", "chimpanzees have less of it", "ditto for dolphins", "reptiles have very little of it", etc. is defining intelligence extensionally. Why is this a problem? Because an extensional definition doesn't tell you how to add new elements to the set.

[hharrison]

I'll try: a system is intelligent if it is able to respond to low-energy deposits (information) with high-energy reactions (e.g., movement) in order to seek non-local sources of negentropy to dissipate.

But then again I'm more interested in the intelligence that differentiates a slime mold from a hurricane than the intelligence that differentiates a human from a chimpanzee.

For example: hurricanes are self-organized, constituted by a structured flow of energy and matter rather than specific pieces of matter. But a hurricane is a slave to the local potential. It will dissipate all the negentropy in its wake, and in doing so maintain its structure. But once there is no more energy differential to dissipate, the hurricane will itself dissipate as it is not able to break free of the local potential and use information to seek out non-local negentropy sources. The question for research is what is necessary to make that jump from self-organization to intelligence, given that operationalization.

[chongli]

Don't wildfires have the ability to break free of a local potential? All it takes is a small spark, carried on the wind.

Likewise for seeds, fish eggs (carried in the gut of birds), etc.

[hharrison]

Wind is a local potential in this example. An intelligent wildfire would be one whose sparks can go against the wind, because it perceives more fuel in that direction.

Also: my definition is meant to include fish and birds, even plants, as intelligent.

[chongli]

I've seen sparks go against the wind, at least on a small scale. Sparks can be launched pretty far when the burning wood falls and breaks apart.

[mkingston]

You've responded to the second part of: "able to respond to low-energy deposits (information) with high-energy reactions (e.g., movement)"

How does your comment about sparks address the alternatively stated requirement: "because it perceives more fuel in that direction"

[chongli]

How do you define perception?

* A spark flies out randomly and contacts a fuel source

* A blind person reaches out randomly and finds a glass of water

What is the essential difference between these events?

[Houshalter]

It's not just arbitrary examples, there is reasoning behind it. You can look at humans building spaceships and using tools and demonstrating understanding of abstract concepts. There are a number of tests you could do that would confirm something is intelligent like looking for any of those things.

Some rough and imperfect, but still useful, definitions of intelligence could be the ability to make good predictions based on past data, the ability to solve optimization problems well, and learning ability.

[chongli]

demonstrating understanding of abstract concepts.

What sort of test can show that a subject demonstrates an understanding of abstract concepts?

So far, from what I've seen, if a test can be written then software can be written to solve the test.

[Houshalter]

You could talk to it or you could have it solve a difficult problem.

[chongli]

Right. That's commonly called the Turing test. This just pushes back the problem of defining intelligence to one of creating a proper Turing test. How do we do that?

[Houshalter]

The Turing test is actually a pretty decent and straightforward test.

I don't understand why this is an issue though. Testing intelligence was never the hard part of AI. There are so many tasks that computers currently suck at that we would be happy if they were solved, regardless what label you gave the solution. And I don't think many people could see a computer doing tasks like having conversations or solving difficult problems and deny that it is intelligence. Even if there is no formal test to perform that is 100% certain.

[chongli]

The Turing test is actually a pretty decent and straightforward test.

How so? To me, it appears completely open-ended. You could sit there forever asking questions and never reach a definitive result.

[eli_gottlieb]

Has anyone bothered to develop a full mathematical definition of "optimization power"? Because I've been thinking about how to do it.

[Houshalter]

http://lesswrong.com/lw/va/measuring_optimization_power/

[eli_gottlieb]

Bugger. That bastard has 10 years' head start on me; simply not fair.

OTOH, looks like not very much was actually formalized.