Last year Baba Shiv, a professor of marketing at Stanford University Business School, played a trick on a group of subjects. He gave them, on separate occasions, the same wine to taste, but at one time he told them that it cost $45 a bottle, and on another $5. And the subjects reported, as they often do in this type of study, that the more expensive wine tasted better.

But Professor Shiv went farther. Using a technique called functional magnetic resonance imaging (fMRI) he examined the deep pleasure centres of his subjects' brains, to discover that they really did light up more with the “expensive” wine. Consequently Professor Shiv entitled his paper Marketing Actions Can Modulate Neural Representations of Experienced Pleasantness.

This is a study with political implications. Politicians tell us that social services such as health or education must be free at the point of use because people are otherwise disincentivised. But the study suggests, rather, that people might dismiss free services as valueless.

Critics could argue the opposite, namely that because Professor Shiv had not charged his subjects - they got the wine for nothing - he had shown that people will value public services precisely because they are expensive but free. But his wine study is only part of a series: two years ago he charged a group of subjects different prices for so-called energy drinks such as Red Bull.

People believe that these “energy drinks” will help their brains to work better, yet subjects who were offered Red Bull at discounted prices managed to solve fewer brain teasers than did those who paid the full price: the price actually affected the purchasers' brain function. Professor Shiv entitled that paper You May Get What You Pay For.

So the political implication is confirmed: people value expensive goods, and - since paying for something reinforces the experience of price - only when people are charged for goods will they continue to value them. Today the gift of a bottle of $45 wine seems wonderful, but if a National Wine Service were to hand out free wine indefinitely, it would soon lose its value.

Private schools, therefore, are better than state schools, private houses are better than council houses, and Harley Street is better than the NHS, not only because the act of paying commands a better service but also because it infuses the consumer with a greater appreciation for that service. We do, indeed, get what we pay for.

Perhaps the saddest lesson of Professor Shiv's study is that it was performed in a business school. The politics departments of our universities, like our legislators, are stuck in 19th century world-views, but business and its schools are deepening our understanding of human nature.

Terence Kealey is a clinical bio-chemist and Vice-Chancellor of the University of Buckingham

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