The Founding Fathers liked happiness so much they considered pursuing it an inalienable right – but maybe that wasn't such a good idea. Happiness seems to make people more selfish, the latest in a series of revelations suggesting it changes how you think – and not in a good way.
Psychologist Joe Forgas at the University of New South Wales in Sydney, Australia, who has led many of these studies, suggests that happiness's negative effects all stem from a cheery mood's tendency to lull you into feeling secure. This makes you look inwards and behave both more selfishly and more carelessly.
"People in a positive mood generally rely more on their own thoughts and preferences, and pay less attention to the outside world and social norms," says Forgas.
To probe the effect of happiness on selfishness, Forgas and his colleague Hui Bing Tan put 45 students into good or bad moods by giving them positive or negative feedback on a "cognitive test" that they had taken. In fact the test was a fake and did not measure cognition, while the feedback bore no relation to their performance.
After using a questionnaire to establish that the volunteers really were happy or sad, Forgas and Tan gave each one 10 raffle tickets for a A$20 prize. The students could choose between sharing some of their tickets with another, hypothetical student or selfishly keeping them all.
On average, those who had been praised kept more raffle tickets.
In a second experiment, Forgas and Tan used film clips to set the mood. Half of a group of 72 students were treated to a 10-minute clip of the British TV comedy Fawlty Towers, whilst the other half endured a passage from the gloomy film Angela's Ashes.
After taking another mood questionnaire, this time the students were shown pictures of a buddy they could share their raffle tickets with – with the intention of making the idea of sharing more vivid than the case of a hypothetical student. Again, the happy students were less likely to share.
Forgas's explanation is that happy people focus more on their own desires. "Positive mood is in a sense an evolutionary signal, subconsciously informing people that the situation they face is safe and non-threatening," he says. This encourages people to rely more on their own thoughts and preferences, with selfishness the result.
Grumpiness or sadness, on the other hand, produces more vigilant, outward-looking thinkers. "A negative mood produces a thinking style that is more detailed and attentive, and pays more attention to the demands of the external environment," says Forgas.
This latest finding adds to a wealth of data suggesting that being happy isn't all it's cracked up to be. In previous studies, Forgas has found that happy people are less able to develop a persuasive argument, more gullible and worse at remembering objects in a shop window than their unhappy fellows.
Happy people are also more likely to be influenced by stereotypes, says Forgas: in another study, happy non-Muslim Australians were more likely to make snap negative judgements about – and even to shoot – computer images of people in traditional Muslim dress.