The conditions of rules are mathced against the currently active portion of memory to identify those rules with conditions that are fully satisified. If more than one rule is mathced, conflict resolution procedures choose only one of these to operate. Go back to Step 1. Production systems have been very influential in cognitive science, and are the basis for many expert systems. This is not easy to do.
Some evidence suggests that frontal lobes are especially important.
Frontoal lobe damage does not produce intellectual impairment as measured by IQ tests. However, it does produce difficulties in solving new problems. In chess, masters are not brighter than duffers. For example, memory studies indicate that experts are better than novices in terms of chunking chess board positions into meaningful units. In Physics Chess conclusions have been confirmed and extended in studies of physics problem solving.