Should I have been more careful or less careless? The comparative nature of counterfactual thoughts alters judgments of their impact.

Counterfactual thoughts inherently imply a comparison of a given reality to an alternative state of affairs. Previous research mainly considered consequences of different counterfactual types, namely focus (other vs. self), structure (additive vs. subtractive), and direction (upward vs. downward). The current work investigates whether a 'more-than' versus 'less-than' comparative nature of counterfactual thoughts alters judgments of their impact. Four experiments demonstrated that self-generated other- (Studies 1 and 3) and self-focused (Study 2) upward counterfactuals are judged more impactful when they entail 'more-than' rather than 'less-than' comparisons. Judgments include plausibility and persuasiveness, as well as counterfactuals' likelihood to change future behavior and feelings. Self-reported ease of thought generation and (dis)fluency gauged by difficulty in thought generation was similarly affected. This more-less asymmetry reversed in Study 3 for downward counterfactual thoughts, with 'less-than' counterfactuals being judged more impactful and easier to generate. Further attesting to the role of ease, when spontaneously generating comparative counterfactuals, participants correctly provided more 'more-than' upward counterfactuals, but more 'less-than' downward counterfactuals (Study 4). These findings delineate one of the to date few conditions for a reversal of the more-less asymmetry and provide support for a correspondence principle, the simulation heuristic, and thus the role of ease in counterfactual thinking. They suggest that especially 'more-than' counterfactuals following negative events, and 'less-than' counterfactuals following positive events, are likely to have an important impact on people. (226 words).