Rationalization in a Reasoning Task.

An experiment is presented to test the dual process model of thinking proposed by Wason & Evans (1975). One prediction of the model is that subjects' introspective justifications of their reasoning behaviour do not reflect insight into the underlying thought processes, but are essentially rationalizations. In the present experiment subjects in independent groups are given one of several different solutions to a reasoning problem as being correct, and asked to justify the solution. As predicted, subjects tend to find reasons for whichever solution is presented and express a generally high degree of confidence in the correctness of their reasons. The discussion relates both the results and the underlying theory to concepts developed by social psychologists.