Fearing the uncertain: Self-uncertainty plays a role in mortality salience

• Mortality salience increased self-uncertainty when self-esteem was not enhanced.
• Mortality salience increased identification when self-esteem was not enhanced.
• Reduced uncertainty attenuates the impact of mortality salience on identification.
• Reduced uncertainty attenuates the impact of mortality salience on ingroup defense.

Two experiments were conducted to examine the relationship between self-uncertainty, self-esteem and mortality salience as they relate to group identification and defense of the ingroup. Experiment 1 (N = 140) tested the hypothesis that self-uncertainty mediates the interactive effect of self-esteem and mortality salience on group identification. Results demonstrated that mortality salience only increased self-uncertainty and identification under neutral self-esteem, and self-uncertainty mediated the interactive effect of mortality salience and self-esteem on ingroup identification. Experiment 2 (N = 294) tested the hypothesis that only when self-uncertainty is elevated does the interactive effect of self-esteem and mortality salience predict group identification and ingroup defense. As hypothesized, when self-uncertainty was reduced TMT results were attenuated. Results across the two experiments demonstrate that self-uncertainty plays a significant role in reactions to mortality salience.