ABSTRACT
The ability to represent structured knowledge and use that knowledge in a systematic way is a very important ingredient of cognition. An often heard criticism of connectionism is that connectionist systems cannot possess that ability. The work reported in this paper demonstrates that a connectionist system can not only represent structured knowledge and display systematic behavior, but can also do so with extreme efficiency. The paper describes a connectionist system that can represent knowledge expressed as rules and facts involving multi-place predicates, and draw limited, but sound, inferences based on this knowledge. The system is extremely efficient — in fact, optimal, as it draws conclusions in time proportional to the length of the proof. Central to this ability of the system is a solution to the variable binding problem. The solution makes use of the notion of a phased clock and exploits the time dimension to create and propagate variable bindings.
