THERE'S something inordinately sexy about ideas on India. What conceptual seductions there are here about modernity-in-change, caste-in-action, Channel V-and-the-bullock-cart and the Manhattan-Mumbai embrace. Sunil Khilnani, 36-year-old Bright-Young-Oxbridge-Indian, has written a celebrated "interpretative and polemical essay", The Idea of India, which has been acclaimed not only by the Western press but even by eminent economist Amartya Sen as "splendid and timely". Says Khilnani, who studied at Cambridge and now teaches politics at Birkbeck College, London University: "Although there is a lot of specialist work on India, there has been little effort to fit it all together, to offer an argument about how the idea of an Indian self was invented by the nationalist generation and how the India idea has developed after 1947."