But he made a humble submission: "In view of the enormity of the problems faced, a trust of this kind can make only a little difference, but I must try to do what I can. I would count on your good wishes in my tiny effort."

In his speech, Sen contested the views expressed by another Nobel laureate Kenneth Arrow and the economic methodologist Lionel Robbins on theissue of social choice.

Discussing Arrow's views on "social choice and individual values" and his "impossibility theorem", Sen said the field of social choice theory looks quite different now. "Instead of the old question `Is it possible to have socially rational decisions based on the interests and preferences of the members of the society?', the new question that has to be addressed in the changes situation is: `Which of the various ways of making socially rational decisions best serve our values of equity and justice?'

The choice is no longer just something, but between many different ways of evaluation among which we can choose by invoking foundational notions such as justice or fairness, he said.

Sen said: "Even the apparently technical subjects of choosing a suitable measure of poverty for a nation or a state can be seen in terms of the competing values which can be reflected in different ways by distinct statistical measures. It is this linking of knowledge with practice that is perhaps the mostencouraging implication of the recent works in welfare economics and social choice theory, including the evaluation of inequality and poverty."

Speaking on Robbins, who had said "every mind is inscrutable to every other mind and no common denominator of feelings is possible", Sen asked: "Is it really so absurd to compare the misery of the thoroughly deprived with the pleasures of the thoroughly affluent? Do we not notice agony and affliction that contrast with the satisfactions of others? More importantly, is well-being really just a mental attribute? Is human welfare nothing other than a feeling?"

"Isn't an economic destitute or a political prisoner or a subjugated housewife or a precarious landless labourer, in some objective way, much more deprived than others more favourably placed? Would not the deprivation of the economic, political or social destitute remain real even if these underdogs manage to build some happiness in their lives?," he asked.

And Sen replied: "If interpersonal comparisons canbe sensibly invoked in terms of substantive deprivations of the opportunity to lead a decent life, then the impossibility results that had threatened rational social choice vanish altogether. The social cynics had not really won. The pessimism was premature."

West Bengal's governor A R Kidwai said Sen has revolutionised the concepts of social welfare and showed the way to maximise human happiness.

Kidwai said: "The World Bank and the IMF release a set of figures relating to national income and the rate of growth of gross domestic product. These numbers have no relevance to the quality of human life in a society."

"A society may have a high per capita income with a very unjust distribution of income. A high GDP does not necessarily imply education and health care for every individual. A famine may occur though there is no shortage of food because the poor have no purchasing power," he said.

West Bengal chief minister Jyoti Basu said Sen has not only broken the barriers in welfare economics, but hasalso applied new concepts, like `capabilities' and `freedom', for studying the problems of famine, availability of food, access to education and public health in the developing economies. The award of the Nobel Prize to Sen is a recognition of his theoretical contribution in the sphere of welfare economics, as also a recognition of the welfare role of the state.