Bloomsbury £18.99 pp448

“The biography of Voltaire has become a palimpsest, each new version being written over the many that have gone before,” says Roger Pearson. His own version of this extraordinary writer, philosophe, human-rights campaigner and entrepreneur is sparklingly witty and eminently readable.

Born François-Marie Arouet in 1694, Voltaire (nobody quite knows why he chose this pseudonym) was a deist — convinced of God’s existence but abhorring Christianity and all organised religion, particularly when it combined with state interests to act as an instrument of oppression. Such an attitude inevitably led him into conflict with the French authorities, both secular and ecclesiastical. Imprisoned in the Bastille more than once, he never felt entirely safe in his native land. Neither did he fare much better in Prussia.

Combative and cantankerous, Voltaire was also (like the eponymous hero of his most famous work, Candide) unfailingly optimistic, sometimes naively so. His greatest love, Emilie du Châtelet (a married woman with an understanding husband), realised how vulnerable this could make him and was constantly at pains to protect him from himself. But he ignored all warnings about entering the service of Frederick the Great, and had to discover the hard way that even an “ enlightened” despot could treat artists and scholars as disposable acquisitions. “One squeezes the orange,” said Frederick, “and one throws away the peel.” Voltaire learnt from this mistake, and preferred to pay court to the other great enlightened despot of the age, Catherine II of Russia, from a safe distance and only in writing.

It was not until after Emilie’s death that Voltaire could reign in his own kingdom, which is effectively what he did at Ferney, the estate near Geneva where he spent his last 20 years. Here he not only put in 15-hour days on his writing while entertaining a stream of admirers at supper, but also used his business acumen to build up a colony of craftsmen. In particular, he supported a group of watchmakers, cajoling his contacts into buying their products. He displayed a talent for making money, first becoming wealthy in 1729 after participating in a lottery scam. This was shortly after the abrupt end to a two- year stay in England, probably over financial scandal. He increased his wealth through money-lending, never allowing principles to stand in the way of profit. An ardent opponent of war, he made a packet from investing in military supplies.

Pearson has a predilection for the sentence fragment (“Much to Emilie’s despair.” or “Which she grants.”), a stylistic tic that can be distracting. I fear that this may be a fashionable way of writing and that my hankering after complete sentences is as outmoded as wishing young men would tuck their shirts in. Voltaire himself cared little for fashion. Describing himself as “thin, tall, dried-up and bony”, he liked in later years to keep his head warm with either an “extravagantly obsolete” wig or with half a dozen silk caps topped by a woolly hat. With his brightly coloured breeches, beaky nose and piercing eyes, he must have resembled a loquacious and quick-witted parrot.

“Was he lovable?” asks the author. Certainly he seems so here. Pearson’s description of Voltaire’s triumphal return to Paris in his last year, when he was crowned with a laurel wreath at the Comédie Française, is moving, and one cannot help but feel, along with the Parisian crowd, that the apotheosis was well deserved. As Pearson justly remarks: “If we are able to take the principles (if not necessarily the reality) of freedom, tolerance and justice more or less for granted in modern western society, it is because people like Voltaire proclaimed their value when the very expression of those views was neither free nor tolerated.”

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