Wednesday, December 06, 2006

More from the slime mould department

And then there's this, which tops even the Roachbot.

Intelligence without Representation II

From the article:
Japanese scientists claim that amoeba-like organisms have a primitive form of intelligence, following an experiment where a slime mould found its way through a maze.

Reporting in the journal Nature, Toshiyuki Nakagaki from the Bio-Mimetic Control Research Centre in Nagoya showed that a slime mould negotiated the shortest route between two exits in a maze, avoiding three longer paths.

"This remarkable process of cellular computation implies that cellular materials can show a primitive intelligence," Dr Nakagaki said.
I think this supports at least two things: one, Brooks' idea that intelligence with representation is not only possible but is also biologically based; and two, that Newell and Simon's symbol system hypothesis holds up. I would definitely call the behavior of this slime mould--when taken as a unified system--intelligent, as it is able to search through a space efficiently to reach a solution. I think, as Brooks would say, that there is intelligent behavior emerging from simple interactions amongst subunits in the system.

(PS: Definitely take a look at the photo; it is very surreal.)

Sunday, November 26, 2006

Intelligence without representation I

Brooks seems to think that behavior based AI will be able to produce intelligence on the level of human intelligence without ever resorting to internal representations at all.

His approach is inspired by evolution, which he says spent most of it's time perfecting perception, "acting and reacting." The things that AI had been primarily concerned with - reasoning, problem solving, language - are very recent developments. So, he says that we should be focusing on acting and reacting before focusing on problem solving.

I think he's right. He's convinced me that we ought to be focusing our attention on acting and reaction without resorting to internal representations of the world. Many of the things we consider intelligent behavior can be produced this way.

But I'm not convinced that language, problem solving, and reasoning can be produced by Brooks' approach. When we communicate with one another or reflect upon our own intenal states, we need symbolic representations. Brooks says that the fact that we use representations when communicating to one another or for introspection is not sufficient grounds to conclude that we have any internal representations to produce behavior.

He might be right. But it's worth pointing out that Brooks's epiphany about abandoning representation came when he realized that the calculations needed just to move a robotic arm was just too complicated. A reactive system with a lot of sensory inputs was able to solve the problem - without the complicated calculations.[*] But what about language? Language is, by its nature, representational. I suspect that getting a system to use language would be simpler if the system had internal representation than if it didn't.

Sunday, November 19, 2006

Consilience

"Philosophers are beginning to like it—it's something for them to do. They've been sort of flopping around since the failure of positivism."
Edward O. Wilson, in an interview with Seed Magazine (November 2006).

The article from which this quote was grabbed is about Wilson's latest book, The Creation, and the rift between science and religion. The book itself is Wilson's attempt to draw the two worlds together in a truce for the sake of humanity's progress, and more specifically to garner attention towards saving the Earth, rather than wasting breath on an argument that goes nowhere. This article is one in a series that spans newspapers and magazines—including Wired's "The Church of the Non-Believers"—that cover a series of books published this fall written by top scientists and philosophers on the subject of fundamentalist values overtaking scientific reason. The authors of these books include Richard Dawkins, Sam Harris, Daniel Dennett, and of course Edward O. Wilson.

The quote above is a reference to the central idea of his 1998 book, Consilience: The Unity of Knowledge, that all fields of knowledge and scientific inquiry are intrinsically linked by a set of fundamental rules implicit to all fields. His remark is in reference to the fact that, after decades of these fields dividing and splintering, there is recent synthesis and convergence where certain fields jut against one another. As members of one field identify similar ideas found in others, they initiate an exchange with their newfound colleagues, which include bridging gaps in each other’s knowledge and linguistic blending.

But doing so is a tedious process. Although the semantic content of related fields develops often along parallel routes, occasionally crossing paths, the syntactical elements progress divergently from the outset, and researchers find themselves unable to communicate effectively with cousins hailing from those neighboring fields. Wilson’s comment hits squarely upon the utility of philosophy emerging in the modern world.

Philosophers have a new task: as catalysts of fusion, to combine the reactant disciplines of science and merge them together into novel, nascent branches of inquiry. Science becomes fragmented as scientists delve deeper into the disparate wells of knowledge, but the philosopher may quickly traverse the many beaten paths, picking up the shards along the way. To fit them together is to fill in the semantic gaps of each domain—and in doing so there occurs a reformulation of content in a new syntax adaptable to the various extant fields, thereby joining them in linguistic solidarity.

PS: For the text of a discussion between E.O. Wilson and Daniel Dennett, click here.