Judgments of intellectual and social attractiveness of a target were taken from a pair of moderate and extreme intellectual or social traits. Weights of the traits given were identified from the pattern in their two-way interaction effect. Responses to a control condition of no-trait information provided the estimates of the person positivity bias in the participants, and the relative effects of the negative and positive traits were determined relative to such bias values. Consistent with the cognitive hypothesis, positive intellectual and negative social traits received more weight in the intellectual and social attraction responses, respectively. However, negative and moderate traits carried more weight in social attraction as predicted by the hypothesis of behavioural adaptation. Despite the asymmetric weighting of intellectual traits in intellectual attraction and of social traits in social attraction, the negativity effect was stronger than the positivity effect. Evidently, mechanisms postulated by both the hypotheses co-exist but they are detectable by only the operationalization employed in the two research paradigms.