How should we study the mind?

In Precursors to Cognitive Psychology we saw that psychologists adopted a number of methodologies throughout the late nineteenth century and the twentieth century, including focusing only on observable behaviour. One early methodology was introspection, which was used to study the elements of perception, although this ran into difficulties. However, for higher-level cognitive processes such as decision making and voluntary behaviour, many social scientists continue to ask people about the reasons for their own behaviour. In a key paper published in 1977, and titled Telling more than we can know: Verbal reports on mental processes, Richard Nisbett and Timothy Wilson reviewed several studies that appeared to show that people are sometimes unaware of the reasons underlying their own behaviour.

In one study, Nisbett and Wilson observed consumers choosing between identical packs of nylon stockings arranged in a row. They found that people were biased towards choosing from the right side of the array but, when asked about their choice, people did not refer to the position of the stockings in the array. When specifically asked whether they might have been affected by the position of the item, almost everybody denied this. Based on this and the results of many other studies, Nisbett and Wilson concluded that people's explanations of their own behaviours were not based on having access to the underlying cognitive processes, but rather were theories about the causes of those behaviours. In other words, people may be aware of the products of their cognitive processes but are not aware of those processes themselves.

Introspections may not always be wrong, but Nisbett and Wilson's analysis indicates that they are not a reliable guide to the causes of behaviour. They may be useful in generating hypotheses, but these should then be subject to