Updating the theory in 2002, Wilson admitted that the 1977 claims had been too far-reaching. He instead relied on the theory that the "adaptive unconscious" does much of the moment-to-moment work of perception and behaviour. When people are asked to report on their mental processes, they cannot access this unconscious activity. However, rather than acknowledge their lack of insight, they confabulate a plausible explanation, and "seem" to be "unaware of their unawareness". The idea that people can be mistaken about their inner functioning is one applied by eliminative materialists. These philosophers suggest that some concepts, including "belief" or "pain" will turn out to be quite different from what is commonly expected as science advances. The faulty guesses that people make to explain their thought processes have been called "causal theories". The causal theories provided after an action will often serve only to justify the person's behaviour in order to relieve cognitive dissonance. That is, a person may not have noticed the true reasons for their behaviour, even when trying to explain it The result is an explanation that mostly merely makes themselves feel better. An example might be a man who mistreats others who have a specific quality because he is embarrassed that he himself has that quality. He may not admit this to himself, instead claiming that his prejudice is because he has concluded that the specific quality is bad. A study conducted by philosopher Eric Schwitzgebel and psychologist Russell T. Hurlburt was set up to measure the extent of introspective accuracy by gathering introspective reports from a single individual who was given the pseudonym "Melanie". Melanie was given a beeper which sounded at random moments, and when it did she had to note what she was currently feeling and thinking. After analyzing the reports the authors had mixed views about the results, the correct interpretation of Melanie's claims and her introspective accuracy. Even after long discussion the two authors disagreed with each other in the closing remarks, Schwitzgebel being pessimistic and Hurlburt optimistic about the reliability of introspection. Nisbett and Wilson conjectured about several factors that they found to contribute to the accuracy of introspective self-reports on cognition. Several hypotheses to explain people's unawareness of their inaccuracies in introspection were provided by Nisbett and Wilson:  The claim that confabulation of justifications evolved to relieve cognitive dissonance is criticized by some evolutionary biologists for assuming the evolution of a mechanism for feeling dissonanced by a lack of justification.