He was travelling by plane to San Diego, once, when the passenger in the seat next to him got talking. On hearing that his travelling companion was from Harvard, the passenger asked: Have you heard of this interesting course on social justice, taught by Kenneth Arrow, John Rawls, and some unknown guy?

That 'unknown guy' went on to become a Nobel Laureate in Economics, in 1998.

		in his words 'There is no question that literacy increases the effectiveness of democracy. But I would certainly dispute the claim that democracy makes no sense if you don't have literacy. That has been the argument dictators have used again and again.'
	Photo: Prakash Singh / AFP/Getty Images

When Time magazine named him on a list of 60 most influential Asians, Lord Meghnad Desai wrote: 'Amartya Sen is not just an Indian or Asian, not just an economist or philosopher. He is a truly global man, cosmopolitan in his sympathies, and universal in his concern for all.'

In his recent controversial book Identity and Violence, the Nobel Laureate argued that some people focus on one aspect of a person's identity and attack the person, even killing him or her. 'What is ignored, deliberately at times, are the common identities the victims and perpetrators of violence share with one another,' Sen said, arguing a case (typically, the name of a previous, equally well received book was The Argumentative Indian) that if the commonalities became the focus instead of the differences, violence would diminish.

The 73-year-old is many things to many people: an Asian, an Indian citizen, a Bengali with Bangladeshi ancestry, an American or British resident (he splits his time between Cambridge, in Britain, and Cambridge, at Harvard, Massachussetts), an economist, a philosophy student, an author, a Sanskritist, a lover of Bengali poetry, a feminist, an atheist, a heterosexual, a defender of gay and lesbian rights, and a Hindu who is a non-believer in an afterlife.

His books -- Collective Choice and Social Welfare (1970), On Economic Inequality (1973, 1997), Poverty and Famines and The Argumentative Indian (2005) -- have ranged, in terms of subject, far beyond his favorite subject, economics, and raised issues of concern to contemporary society.

Yet it is as an economist that Amartya Sen -- who received his name from another Nobel Laureate, Rabindranath Tagore -- has had the most profound influence. Acknowledging his contributions to welfare economics, the Royal Swedish Academy of Sciences said, in the Nobel citation, that 'Amartya Sen has made several key contributions to the research on fundamental problems in welfare economics. His contributions range from axiomatic theory of social choice, over definitions of welfare and poverty indexes, to empirical studies of famine. They are tied closely together by a general interest in distributional issues and a particular interest in the most impoverished members of society.'

While the dry prose provides an adequate summation of Sen's achievements, Lord Desai best describes the reason for the economist's influence on contemporary society: 'Sen is special because he is the first economist-philosopher whose work has consciously touched the lives of millions of the poorest people in the world,' Lord Desai wrote in Time. 'His Poverty and Famines has changed the way famines are understood and cured.'

Sen, who has found fault even with Communist countries for not preventing famine, has demonstrated, following years of study, that people die during famines not because there is no food but because they do not have the resources to buy food. His status as contemporary thinker is colossal; yet his reputation on campus at Harvard is that of a jolly good fellow, ever ready for some impromptu poetry reading, a brisk bike ride -- or a crisp, hard-hitting argument.