The present research shows that although people believe that learning more about others leads to greater liking, more information about others leads, on average, to less liking. Thus, ambiguity–lacking information about another–leads to liking, whereas familiarity–acquiring more information–can breed contempt. This “less is more” effect is due to the cascading nature of dissimilarity: Once evidence of dissimilarity is encountered, subsequent information is more likely to be interpreted as further evidence of dissimilarity, leading to decreased liking. The authors document the negative relationship between knowledge and liking in laboratory studies and with pre- and postdate data from online daters, while showing the mediating role of dissimilarity