More than 1,000 statisticians and economists were Saturday winding up four days of talks in Istanbul devoted to two of mankind's most intractable questions: what is happiness and how do you measure it?
Experts attending a forum of the Organisation for Economic Cooperation and Development acknowledged that the indices used in the past, which depended basically on economic data such as national wealth and Gross Domestic Product, were no longer valid.
"Because we measure GDP per capita, then we believe that we know if people are satisfied or not," OECD Secretary General Jose Angel Gurria told the forum on "Statistics, Knowledge and Policy."
"But how well informed are in fact the leaders about what people want, feel and believe? We must seek tools that can improve rational policy-making."
Professor Ruut Veenhoven of Erasmus University in Rotterdam said that in future statistics had to take into account how happy people felt they were.
Those surveyed had to reply to a simple question: "To what extent are you at present happy with your life?" They had to give it a mark out of 10.
Veenhoven, who heads the World Database on Happiness, has compiled figures for 95 countries.
It turns out that the happiest folk on the face of the Earth are the citizens of Denmark who give themselves an average of 8.2 out of 10. The least happy people are Tanzanians who score 3.2 while the United States occupies 17th position and Russia 84th.
"The happy countries are rich, they have a competitive economy, they are democratic, they are well governed -- irrespective of the regime they have good bureaucrats, open, responsive and not corrupt -- there is gender equality and there is tolerance, and so people are free in these societies to seek that way of life that fits them best," said Veenhoven.
In terms of individuals, married people are in general more happy than singles but the index drops with the arrival of children, women's liberation has done more for men's happiness than for women's, and the higher the educational level the less likely the individual is to be happy.
Apart from their value of snapshots of society, data such as these could one day influence government decisions.
"You can ask people about happiness in various domains of their lives, then you can go to further subdomains to know what is the impact of government policies," according to Professor Richard Layard of the London School of Economics.
Calculating happiness is still at the experimental stage but, Layard thinks, could one day be a more useful policy tool than opinion polls.
"We are trying to find out what the government policies actually did to them, not how they judge the government policies."
Another promising line of inquiry is neurology, which statisticians could enlist as a tool.
"We can link more and more neurological kinds of research with happiness research coming from social sciences and psychology and we'll learn much more about the structure of human beings," said Gert Wagner of the German Institute of Economic Research.
"But this is nothing for politicians," he hastened to add, ruling out the prospect that governments could plug into their citizens' brains to make them happy.