ABSTRACT
For developing and empirically evaluating models of human cognition, a levels approach towards cognitive modeling is proposed in this chapter. Several prominent researchers have asserted that the human cognitive system cannot be appropriately described as a physical symbol system and have thereby challenged one of the most fundamental assumptions of traditional cognitive psychology. In the levels approach to cognitive modeling, symbol-level descriptions thus characterize the symbols, symbol structures, and cognitive processes of human learners in specific situations. Propositions are good examples of such symbols. The textbase and situation model would be examples of symbol structures, and the formation of a textbase can be taken as an example for a cognitive process in a symbol-level description. The goal of learning is defined in relation to unknown problem-solving situations. In particular, a cognitive system engages in learning in order to acquire knowledge that will assist in solving future problems.
