Two field experiments examine the attitudinal consequences of consumers changing their minds about previously seeing brands when in fact they have not. In the first study, an increase in false brand awareness, holding brand exposure constant, is found to result in more favorable brand attitudes. In the second study, changes in false brand awareness were found to mediate the development of defensive thoughts in which respondents self-justify changing their minds. Defensive thoughts, in turn, mediate the development of brand attitudes. The results suggest that simple changes in one's subjective probability of previously seeing a brand independent of actual exposure can have significant attitudinal consequences for that brand. This is due to the generation of self-justifying cognitions. Individual change scores are further found to have greater theoretical and empirical utility than static measures. © 2011 Wiley Periodicals, Inc.