Introspection is not fully inept. People do know the contents of their minds. That is, they do know what they think, what their attitudes are, what their emotions are. Introspection works fine as a way of knowing what the current contents of one’s mind are. But people do not know how they arrived at those contents. A sincere answer to ‘What are you feeling right now?” is likely to be accurate, whereas a sincere answer to ‘Why do you feel that way?” is much less reliable.
~Roy Baumeister, The Cultural Animal, p. 220-221