Deception plays a big role in the relationship between teachers and their pupils. Just think of all those implausible reasons why homework can't be handed in on time. Left it on the bus. Cat ate it. Computer struck by lightning. But we tend to collude with deception because there are strong emotional reasons for doing so. Freud argued that some truths are too painful to know, so we forget them, project them, sublimate them or distort them into a form we can bear. Why else do we overlook our partners' blatant infidelities or exchange pleasantries with people we detest?
This type of behaviour is becoming the focus of research on lie detection.
A recent study by a team of psychologists led by Julian Keenan of Montclair State University in New Jersey found women not in committed relationships were significantly better at detecting males "faking good": making up qualities that they didn't have. It's widely known that women are more attracted to men who have greater "resource allocation" potential (that is, rich men with prestigious jobs). It follows that men may be motivated to "fake good" and tell lies such as the Ferrari outside really is theirs and not just borrowed for the night from a friend.
Evolutionary psychology suggests that women detect male deception if they are thinking of having a child. Mixing your genes with a man who only borrows a Ferrari rather than owns one has, theoretically, negative evolutionary implications. On the other hand, if you already have children or are pregnant, then it's possible you are in a phase in the relationship where you are motivated not to see deception. So it follows that women who are not in a committed relationship should be better at detecting men "faking good". And consistent with evolutionary psychological theory, the psychologists found they were.
Working out what is going on in other people's minds is called Theory of Mind, or ToM (see my column on June 3). Because intentional deception requires you to understand the mental state of others (ToM), a positive relationship between self-awareness and the ability to deceive seems to follow. For example, children's ability to deceive emerges shortly after they develop self-awareness, as indicated by self-recognition, their use of self-pronouns, and self-conscious emotions. Further, groups of people without self-awareness (such as schizophrenic patients) don't appear to be good at lying or spotting deception. The Montclair group are about to publish a new study that finds those with higher private self-awareness are also more effective deceivers.
The study, called "Me, Myself, and Lie: the role of self-awareness in deception" and soon to be published in the journal Personality and Individual Differences, involved a group of people with a range of scores on self-awareness tests who then lied on videotape. This was played to undergraduate students who had to determine when they were lying and when they were telling the truth.
The study's findings are intriguing, but it is notable how much less psychological research has been conducted on what makes a good liar as opposed to the plethora of work on how to spot deception. Perhaps there is a basic problem in recruiting great liars: volunteering for any such group wouldn't do a lot for your reputation.
Dr Raj Persaud is Gresham professor for public understanding of psychiatry, and director of the Centre for Public Engagement, King's College London.
His latest book is The Motivated Mind (Bantam Press). Email: firstname.lastname@example.org