The current research shows that people differ in their inclination to use positive self-images when their self is threatened (i.e., cognitive self-affirmation inclination, CSAI). Just as self-affirmation manipulations do, the use of positive self-images induces open mindedness towards threatening messages. The aim of the current studies was to show the meaning, stability, and effects of this new individual difference measure. A cross-sectional study among smokers (Study 1) showed that people with a strong CSAI perceived more negative consequences from smoking, suggesting open mindedness. Study 2 showed the stable and reliable character of the CSAI scale. Study 3 showed that the scale had an overlap of 18% with another self-related construct (self-efficacy) and no relation with self-consciousness. Study 4 showed that for induced self-threats a strong CSAI led to the same pattern of persuasion as found in earlier studies on self-affirmation manipulations. Study 5 showed that a self-affirmation manipulation did not have any effect for those participants with a strong self-affirmation inclination, probably because they already had access to positive self-images. Study 6 showed that self-reported positive self-images mediated the effect of self-affirmation inclination on persuasion.