Descartes, by A C Grayling

I spy, with my philsopher's eye...

It's not easy to say. Grayling is many sided (as was Nietzsche): pre-eminently a philosopher, he is also esteemed as a writer, broadcaster, critic and a director of the hugely admired current affairs magazine, Prospect. In this biography of Descartes, he attempts to fathom another many-sided man by studying what is available concerning his life and times, rather than dwelling on his writings as a mathematician, scientist and philosopher. In doing so he suggests an intriguing, additional side to the 17th-century "father of modern philosophy", hitherto unsuspected: that René Descartes was a Jesuit spy.

The fact that it is all theory and circumstantial "evidence" does not detract from the book as a wonderfully spun detective story. Grayling concedes again and again that his suggestions of espionage, perhaps undertaken in order to stay out of trouble at a time of fierce religious conflict, "amount to no more than a guess". So, while it's left to readers to assess the author's surmise, we can't accuse him of craftily christening truth. Yet I, for one, am not terribly convinced that to Descartes' famous discovery, "Cogito, ergo sum" (I think, therefore I am) we may add "Speculo, ergo supero" (I spy, therefore I survive).

Any study of Descartes is fraught with missing links, contradictions and, of course, big questions. Was he, for example, a Roman Catholic apologist mainly concerned with supporting Christian dogma, or an atheist bent on protecting himself with pious sentiments while establishing a deterministic, mechanistic and materialistic physics? Such questions were raised while the philosopher was alive, and continue to defy clear answers, largely because many of his papers and manuscripts are lost. As Grayling reminds us, autobiographical details in Descartes's Discourse on Method are "very sketchy". Among apparent contradictions is the fact that Descartes was entirely loyal to the Jesuit order which educated him and which forbade communication in any language but Latin, yet he published Discourse in French.

Descartes certainly was an odd chap. Born in Touraine in 1596, as a small boy he was attracted to cross-eyed girls. He was in delicate health and could not cope with the cold. The American historian James Harvey Robinson, among others, has Descartes in Bavaria, "sitting by the stove" wondering what to believe. Bertrand Russell, on the other hand, places him in the stove, "staying there all day meditating" (Bavarian stoves, apparently, were capacious enough for that in those days).

These were indeed perilous times. The so-called Thirty Years' War, or Wars of Religion, began just as Descartes was finishing his Jesuit education. As Professor Grayling says, the details of the young Frenchman's military service and travels during this period are "extremely scanty". In 1928, however, we know that Descartes had a private audience with Cardinal de Bérulle, a "notorious" leading figure in French politics, and then went into "permanent, and apparently self-imposed, exile" in the United Provinces of Protestant Holland.

A standard explanation is that the young philosopher needed privacy and seclusion for his work. Another is that, although a Catholic, he glorified reason, shared a number of Rosicrucian goals, came from a Huguenot province and favoured religious tolerance (all anathema to the likes of Bérulle) and so was vulnerable to attack in France. Bertrand Russell shared that "fear of persecution" theory.

But Grayling's suggestion is that Descartes was in some way engaged in intelligence activities or secret work during the period of his military service and travels, and that, consequently, Bérulle warned him to leave France. If Descartes was an agent, the author goes on, "he was by far most probably so in the Jesuit interest" which was to reclaim for Catholicism those parts of Europe lost to Protestantism.

Grayling contemplates an additional twist in this enthralling narrative: that, in return for being allowed to leave France for liberal exile, Descartes "abjured any activities inconsistent with French interests... The secrecy of his movements and addresses for his first years in the Netherlands would then need to be explained not as anxiety to avoid French government hostility or surveillance, but the attentions of individuals who might have come to bear grudges as a result of his activities in the hypothesised role."

Although I have concentrated on the Cartesian spy aspect, the biography should not be judged on that alone. It is, notwithstanding the lost papers and manuscripts, an intimate and enlightening picture of Europe in tumult and of a "solitary" and "prickly" genius who eventually succumbed to the low temperatures he abhorred. Unable to endure the winter in Sweden where he unwisely had gone to tutor Queen Christina, Descartes got pneumonia and died in 1650.