Analysis and Rationality
Summary. Some recent experimental results in psychology are claimed to demonstrate an inherent human tendency to commit certain fallacies in deductive reasoning. But these results are open to alternative and more plausible interpretations, because we can tell the meaning that a person attaches to a logical term only when we know the structure of the inferences that he is inclined to make in contexts in which it occurs. So the results of experimental tests on deductive performance should not be taken to cast any discredit on appeals to intuition in philosophical reasoning.
EVERY replicable intuition, we have seen (§§ 8-14), is a piece of primafacie evidence about the norms of valid inference. But it is not always easy to reconcile all our intuitions within a comprehensive system of norms and some have to be discounted--by one or other of various characteristically inductive procedures that were described in § 11. Is this the way in which logically and statistically uneducated people should treat any mistakes they make in deductive or probabilistic reasoning--a species of mistake to which some contemporary psychologists claim them to be especially prone? If it were, then the credentials of intuition, as a source of premisses for philosophical reasoning, would not be seriously tainted. After being filtered through whatever procedures of discounting were appropriate, people's surviving intuitions would support principles of reasoning that are both normatively acceptable and, under ideal conditions, psychologically effective.
But that is not how these psychologists see the situation. They claim that many of the mistakes that an ordinary person makes are not due to adventitious motivational or intellectual preoccupations, but are systematically generated by his possession of normatively incorrect principles or by his non-possession of correct ones. So, if such a person used his own intuitions as a basis for analytical philosophy, he would arrive by impeccable inductive reasoning at seriously erroneous conclusions. Hence, if the psychologists were right, what they