Accessibility experiences and the hindsight bias: I knew it all along versus it could never have happened.

In two experiments, we tested accessibility experiences versus accessible content in influencing the hindsight bias when participants generated either thoughts about alternative outcomes or thoughts about known outcomes. Participants who had listed many thoughts (Experiment 1) and those who had contracted their brow muscles (Experiment 2) when considering alternate outcomes rated the known outcome as more likely than did than those who had listed two thoughts or who had not contracted their brows--a "backfire" effect. In contrast, but no less ironically, participants who had listed many thoughts and those who contracted their brows when considering known outcomes rated those outcomes as less likely--an "it could never have happened" effect. Both effects are due to subjective accessibility experiences, and their role in influencing and debiasing the hindsight bias is discussed.