Polyscheme | Human-Level Intelligence Laboratory
Overview paper (somewhat dated).
Explaining the breadth of human cognition
An important aspect of human-level intelligence is the wide range of situations it can deal with. It is important to explain not only cognition in specific situations, but the potential of human higher-order cognition to deal with new kinds of objects and situations. What enables human cognition about parliaments, interest rates, automobiles and complex numbers while none of these existed when the human brain involved? What cognitive mechanisms enable people, especially children, to learn about and deal with new kinds of objects and events? How is cognition involving multiple domains integrated (as, for example, when inferring the psychological, social and legal effects of a physical action) so effortlessly?
Cognitive Substrate Hypothesis
One answer to these questions is (a) that humans have a basic set of representation, reasoning and problems solving mechanisms, which we call a cognitive substrate, (b) that they use in cognition about objects and events in most or all domains and (c) that learning to deal with a new domain involves learning how to represent entities in that domain in terms of the representations used by the cognitive substrate.
Support
Our motivation for the cognitive substrate and our initial guess at what specific mechanisms constitute it stem from results in linguistic semantics and cognitive psychology together with some evolutionary considerations. First, when the human brain evolved, most of what concerned people involved social and physical relations. Thus, the mechanisms that support human physical and social cognition must be powerful enough to support cognition in the wide variety of domains people operate within. This conclusion is also supported by work in linguistic semantics that shows, for example, how concepts of physical force and motion can be used to represent many other (often abstract) semantic fields such as those involving possession, psychological events and time.
Implementation
Our initial hypothesis about the contents of the cognitive substrate is based on the just mentioned research indicating dualities between physical and abstract representations in cognition. We have implemented a cognitive substrate using the Polyscheme cognitive architecture that includes mechanisms for reasoning about times, spatial relationships, part relations, categories, identity, events and alternate states of the world.
Mappings
Part of our work on the Cognitive Substrate is to show how the cognition in many domains can be reduced to reasoning in the cognitive substrate. We have shown (as illustrated in the diagram above) that the grammatical structure of sentence can be captured purely in terms of substrate relations. We have also shown that reasoning about the beliefs of people in many cases can be conducted using only mechanisms involving identity, counterfactual worlds and categorization.