Books: Three Horsemen of the New Apocalypse by Nirad C Chaudhuri Oxford University Press, pounds 10.99 In Light of India by Octavio Paz Harvill, pounds 9.99

Sages in their time; Sunil Khilnani enjoys a cosmopolitan outlook with the Indian who went west and the Mexican who looked east

Combined, the ages of Nirad Chaudhuri and Octavio Paz add up to 183 years - years each has devoted to refining a high, supremely cosmopolitan civility. Like most ultra-civilised men, they despair at what they see as the West's decline into mediocrity. Chaudhuri has made despair the lifelong theme of his thought and writing; for Paz, it has served as an incitement to discover and celebrate all that takes one away from the vulgarity of western civilisation. These two small books distil the passion and obsessions of these grand old men.

Chaudhuri, born exactly 100 years ago, is the last, greatest avatar of the Bengali Bhadralok: a self-engendered enlightened aristocracy which "created the culture now recognised as the modern Indian culture". His is one of the truly fascinating 20th-century Indian lives. Rooted in his Bengali culture ("even in England, I am in my dhoti when at home"), he always remained a fervent loyalist to the imperial idea and chose to leave his own free country to settle in Oxford. There he spent his life mourning an England that has become niggardly, licentious, unable to speak its own language.

Chaudhuri is an Augustan who has wandered into a postmodern world, a man whose ear is more attuned to hearing the clang of Spartan pickaxes as they demolished the walls of Athens than the electronic gurgles of the video arcade. Writing in his 99th year, Chaudhuri suspects that readers may "expect only senile babbling from me". In fact, his prose has a schoolmaster's finickiness, always careful to define and instruct. After describing his method - a parsimonious reduction of everything to its simplest terms - he moves to his real theme, the three horsemen who portend doom for western - and hence world - civilisation: individualism, nationalism, and democracy.

Yet Chaudhuri is caught in paradox. An anti-individualist, he is a highly idiosyncratic character, only able to live the life of his own choice in the individualist West; a critic of the decadence democracy spreads, he is a beneficiary of its extension of the fruits of civilisation to all. What distinguishes him from many others who feel they live in an untimely world is his deep humanism: this has always saved him from the authoritarian posturing that many Cassandras adopt.

Octavio Paz, like Chaudhuri, is a universalist, believing in a single civilisation and interested in connections between cultures. But where Chaudhuri has perfected an unrelentingly dry, rationalist style, Paz is a lyricist, a seducer of language. India, which he first visited in 1951 and returned to 11 years later to head the Mexican embassy in Delhi, has deeply marked his life and work. His essay, an attempt by a Mexican writer to make sense of the "immense reality of India", is a billet doux to India and Indians.

Paz also sets himself the task of explaining India to outsiders. So there are dutiful trots through the intricacies of caste, religions, languages, and history, and the difficulties faced in making an ancient, diverse civilisation into a nation. Along the way, Paz spins an imaginative, speculative geography of routes that may once have linked Mexico and India - giving both cultures a love of chillies, curries, loose clothing, and a complicated relationship between past and present. It is the contrasts, though, that he stresses. Mexico is caught in a "historical solitude"; India was always a crossroads through which ideas and cultures passed, so ensuring that - as E P Thompson once put it - "there is no thought in the West or East that is not active in some Indian mind".

There is much to learn from Paz's keen observations, yet as he writes, "India did not enter me through my mind but through my senses". His writing comes alive in his descriptions, and especially in a wonderful discussion of classical Sanskrit poetry and philosophy which superbly demonstrates the clarity, eroticism, soft irony and transforming luxuriousness of this poetry. The epigrammatic, sly precision through which the great Sanskritic themes are given poetic form - the merging of male and female, the dissolution of the self - are repeatedly illustrated in quotations: "The lamp of love had almost reached nirvana/but it wanted to see what those two would do/when they were doing it: curious, it stretched its neck/and, seeing what it saw, let out a puff of smoke".