When people cannot access the real cause of their behavior, they do not say 'I don't know'; they generate a plausible-sounding reason and sincerely believe it. The explanation feels like introspection but is actually a story constructed after the action to preserve a sense of a coherent, rational self.
Once an outcome is known, the mind revises its memory of prior expectations to make the result seem inevitable and foreseeable. This 'I knew it all along' effect erases the genuine uncertainty you felt beforehand, making you overrate the predictability of events and your own past judgment.
People do not weigh evidence neutrally; they seek out, notice, and remember information that supports what they already believe while discounting or ignoring what contradicts it. The result is that exposure to more information often entrenches a prior belief rather than correcting it.
People judge how likely or common something is by how easily examples come to mind, not by actual frequency. Because vivid, recent, or emotionally charged events (plane crashes, shark attacks) are easier to recall, they are systematically overestimated relative to duller but more frequent dangers.
The book cites Capgras delusion, in which a patient with damage disconnecting face recognition from emotional response looks at a parent and recognizes the face but feels no familiarity, so concludes the person must be an identical impostor. It is offered as evidence that the normal sense of 'knowing' someone is a constructed feeling, not a direct perception of fact.