Nisbett & Wilson (1977)
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Nisbett, R., & Wilson, T. (1977). Telling more than we can know: Verbal reports on mental processes. Psychological Review, 84, 231-259.
Although people can usually produce an explanation for their behavior, that explanation may not be accurate because people do not have direct introspective access to many (if not most) of their mental processes. "Telling more than we can know" refers to a potential problem with using self-report methods to study mental processes: Participants may be telling the experimenter more than they could be expected to know about themselves. Nisbett and Wilson review several studies that provide evidence supporting this claim. The basic methodology in these studies is to experimentally manipulate the cause of a participant's behavior, ask the participant to explain their behavior, and find that the participant produces an explanation that does not involve the experimental manipulation.
This article is considered a classic in social psychology and is a percursor to the contemporary field of automatic