A degree of happiness at glum Harvard

A sociology professor at Harvard University, Nicholas Christakis (pictured), has discovered that happiness is contagious. In a report published today by the British Medical Journal, Christakis finds that happiness can spread like a virus through social networks, extending up to three degrees of separation: in other words, to the friends of one's friend's friends.

Christakis concludes: "People's happiness depends on the happiness of others with whom they are connected. This provides further justification for seeing happiness, like health, as a collective phenomenon."

Observers from the 'bleeding obvious' school of cynicism will be interested to know that Christakis's findings, based on 20 years of research, are published in the very week that Harvard president Drew Faust had to issue a warning about budget cuts at the university because he current financial crisis has hit funding.

The Harvard endowment - the biggest of any university in the world - stood at $36.9 billion at the end of June. Since then, falling investment values have reduced that money-pot by $8 billion in only four months, and Ms Faust warns that the university must plan for a total $12 billion fall over the fiscal year. In a letter to Harvard's deans, she blamed "severe turmoil in the world's financial markets".

Thankfully, Christakis's report shows that unhappiness is not nearly as contagious as happiness. "Unhappiness doesn't spread as intensely or as consistently as happiness," says the professor. ·