The present studies explore how activating concepts pertaining to the origins of interindividual differences affect the processing of stereotypical and counterstereotypical information. The concepts, i.e., nature and nurture, are both assumed to evoke similar stereotypical expectations although nurture implies greater flexibility. The studies show that stereotypical information enhances whereas counterstereotypical information diminishes stereotyping when nurture is activated. In contrast, counterstereotypical evidence challenges what activated nature would suggest and perceivers primed with nature evince stronger stereotyping when they encounter counterstereotypical information. The results also show that priming nature leads perceivers to attribute stereotype conformity to internal causes whereas nurture accredits conformity to situational constraints. Stereotype flexibility is associated with the subjective ease with which perceivers can both imagine counterstereotypical and mentally undo stereotypical evidence.