People generally judge the personalities of attractive people more accurately than those of others.

Researchers had volunteers socialise in groups of five to 11 people in Canada. Each person talked with every other person for three minutes. After each chat, the participants rated the other person's physical attractiveness and five major personality traits - openness, conscientiousness, extraversion, agreeableness and neuroticism.

Overall, the personalities of people considered physically attractive were rated more accurately. This may be because people are more motivated to pay attention to attractive people.

One does judge a book by its cover, but a beautiful book leads you to read it more closely. However, this research about first impressions may not hold true for people who have known each other for a longer time.