In an expert system, if a rule is wrong, it is worthless if not downright harmful). For people, however, even if a generalization is wrong, that does not mean it is useless. Our memories use generalizations for three distinct purposes:
When a generilization provides incorrect expectations, it has only failed in the first purpose. The incorrect expectation actually serves to further the other two purposes. It allows us to upgrade whatever theory of ours failed and it gives us a place to index the new case, along with its explanation.
Learning and Memory
Where am I in the content of the book?