Each AGI project that has ever existed seems to have (or have had) its own definition of what intelligence exactly is, although some are more exact than others. Some are similar, some are starkly original, many fall into conceptual groups. And even when researchers write approvingly of another project’s definition, they still deign to conjure one of their own. Of course, i’m no exception. And why not? The system i’m writing is different. Why shouldn’t my working definition be different too?
But let’s look at some existing definitions:
Intelligence is the capacity of a system to adapt to its environment while operating with insufficient knowledge and resources. – Pei Wang
General Intelligence is the ability to achieve complex goals in complex environments. – Ben Goertzel
Intelligence deals with all the things which should be known in advance of initiating a course of action. – The Clark Task Force of the Hoover Commission
Great. What are we waiting for? Let’s build it.
Oh, but… we just just took the amorphous word “intelligence” and “defined” it using a bunch of equally amorphous terms: environment, insufficient, knowledge, goals, complex, things, action. (More definitions can be found here.) Naturally, the authors of these definitions continue on in their texts going to great pains to resolve this, but we still end up with something unsatiating, or perhaps even worse: a concrete definition. Something, say, like this: “Intelligence is the sum of all properties where the first derivative of the definite function of the extensional intersection of confident statements is zero, thus maximizing the current goal predicate.” (Note: this just came out of my cerebral blender. No one actually made this statement. But, could you tell?)
Others take a different approach. Rather than even attempt to reduce intelligence to 20 words or less, they merely provide a list of requirements: autonomous, goal-directed, learning, adaptive, capacity for reason and abstract thought, capacity for knowledge and the ability to acquire it, ability to solve problems. More amorphous words. (No, i did not just learn the word “amorphous” today. But i admit i haven’t had much of a chance to use it in the past.) Clearly, we’re no better off.
Some commentators say that the word “intelligence” itself is steeped in human experience, and so could only hope to describe human intelligence, and subjectively at that. This is a valid argument, especially since it seems widely accepted that there is a substantial difference between human intelligence and general intelligence. But now our question becomes even harder. Now we need to create a definition of a concept that we don’t even understand in ourselves, much less in some general sense.
The answer still eludes, but the method of finding it is sound. Let everyone submit their own hypotheses, build systems based upon them, and see what happens. After all, the soil in which human knowledge grows is fertilized by ideas that made sense at the time. And there’s no doubt this soil is fertile, having decomposed ideas for roughly 60 years now.
And so without further ado, i present the latest version of my own working definition:
Intelligence is the system that allows an agent to discover predictable patterns in its environment, which it can thereafter use to maximize its goals. – Matthew Lohbihler
And now, let me try to nail down the Jello™ words.
- System: a software application running on a computer, or a biological brain, or anything else someone may want to try.
- Pattern: a set of spatial-temporal events detectable by the agent’s senses. E.g. a stationary or moving scene, a sound, a tactile sensation, etc. Patterns can be built up in hierarchies to produce more abstract patterns, i.e. sounds into phonemes into words into sentences into ideas.
- Environment: the universe of possible sensory input the agent can experience.
- Goals: motivations that carry benefits for the agent. First order examples are food/nourishment and sex/reproduction corresponding to ontological and phlogenical survival respectively. Higher order examples include social cooperation and social domination. Pathological examples include drug additions and gambling. Come to think of it, there could be “zero-th order” motivations that they all fold into: the release of dopamine and other neurotransmitters that act as the most basic reward/punishment mechanisms of the brain.
(To me the rest of the words are self-explanatory, but i’ve been ruminating on this definition for a long time. Add a comment if you would like more explanation.)
This definition allows a continuum of intelligence. It doesn’t need to be there or not. Obviously, non-humans have some degree of intelligence; it’s accepted that humans are simply more intelligent than apes, not that humans are intelligent and apes are not. Thus, the capacity for intelligence exists in all animals, just to different degrees. Also, intelligence can take many forms depending upon the senses and the capacity for discovery, storage, and utility of pattern unique to the animal. On this scale, insects often seem to be void of intelligence since they appear to lack the capacity to learn patterns: they just recognize and react to the patterns that are hard-coded into their genomes. But bees may have short-term intelligence in that they can remember the locations of food sources and communicate this information to comrades. Humans take it to whole new levels.
But intelligence levels do not necessarily climb as species evolve. Evolutionary neurology seems to be a struggle between the flexibility of intelligence, and the efficiency of hard-coding. In survival terms, intellectual capacity is very expensive. (About 30% of all the calories you consume go to keeping your relatively massive brain running.) And so in practice we regularly see that animals have as little intelligence as they can get away with.
This also provides a nearly plausible explanation for why we still haven’t built an AGI in a computer: it’s too easy not to build it. Narrow systems built for specialized purposes (spreadsheets, e-commerce web sites, global weather simulations, data mining) are multiple orders of magnitude more efficient in CPU, memory, and human developer utilization than the most efficient AGI that we can currently imagine.