Over 50 years ago, psychologist Charles Osgood developed an influential method, known as the 'semantic differential', that attempts to measure the connotative, emotional meaning of a word or concept. Osgood found that about 50 per cent of the variation in a large number of ratings that people made about words and concepts could be captured using just three summary dimensions: 'evaluation' (how nice or good the object is), 'potency' (how strong or powerful an object is) and 'activity' (whether the object is active, unpredictable or chaotic). So, half of a concept's meaning is simply a measure of how nice, strong, and active it is. The main problem is that, until now, no one knew why.

Dr Baddeley explained: "Over time, we keep a running tally of all the good and bad things associated with a particular object. Later, when faced with a decision, we can simply choose the option that in the past has been associated with more good things than bad. This dimension of choice sounds very much like the 'evaluation' dimension of the semantic differential."

To test this, the researchers needed to estimate the number of good or bad things happening. At first sight, estimating this across a wide range of contexts and concepts seems impossible; someone would need to be observed throughout his or her lifetime and, for each of a large range of contexts and concepts, the number of times good and bad things happened recorded. Fortunately, a more practical solution is provided by the recent phenomenon of internet blogs, which describe aspects of people's lives and are also searchable. Sure enough, after analysing millions of blog entries, the researchers found that the evaluation dimension was a very good predictor of whether a particular word was found in blogs describing good situations or bad.

This way of quantifying risk is called 'value at risk' in financial circles, and the perils of ignoring it have been plain to see. Russian Roulette may be, on average, associated with positive rewards, but the risks associated with it are not for everyone! ... Again, this different kind of risk is relevant in financial dealings and is often called volatility. It seems that the mistake that was made in the credit crunch was not ignoring this kind of risk, but to assume that you could perfectly guess it based on how unpredictable it had been in the past.

Lew was at Citigroup from 2006 to 2009 as the financial crisis hit, and he received a $940,000 bonus, just as the giant bank received a government bailout. Asked whether it was immoral to accept the bonus, Lew, said he'd performed well for the company during that period.

¶ 5:43 AM