Voltaire in love...

Love and the Enlightenment

The woman behind the man

May 18th 2006
From The Economist print edition

Emilie du Châtelet was a lot cleverer than her great lover, Voltaire

EVERYONE, just about, has heard something about Voltaire, and most of it is flattering. Freethinker, dramatist, poet, scientist, economist, spy, politician and successful speculator to boot, he embodies the intellectual breakthrough of the Enlightenment—the single biggest leap in mankind's understanding of itself and the world.

Almost nobody has heard of the woman with whom he shared most of his life, Emilie du Châtelet. But you can make a good case that she was a more rigorous thinker, a better writer, a more systematic scientist, a formidable mathematician, a wizard gambler, a more faithful lover and a much kinder and deeper person. And she did all this despite being born a woman in a society where female education was both scant and flimsy. Her mother feared that anything more academic than etiquette lessons would make her daughter unmarriageable.

David Bodanis's new biography of Emilie, Marquise du Châtelet, is a belated treatment of a startlingly neglected story. One reason was male chauvinism. Her best work was done at a time when women simply did not feature in the scientific mainstream: Immanuel Kant said that counting Emilie as a great thinker was as preposterous as imagining a bearded woman. Biographers were much more interested in Voltaire himself; his sexy mistress was just a sidekick. Most writers who did research Emilie were too scientifically illiterate to understand her significance. Nancy Mitford's 1957 novel, “Voltaire in Love”, is a prime example. “Mitford knew as much about science as a shrub,” notes the author scornfully. Mr Bodanis, a former academic whose previous book, “Electric Universe” has just won the 2006 Aventis prize for science writing, is well placed to appreciate the extraordinary scope and scale of her work, and leaves the reader in no doubt of it.

Born in 1706, Emilie had three pieces of great good fortune in her life. The first was to be born with a remarkable brain. Her greatest work was to translate the “Principia”, the path-breaking work on physics by the secretive Cambridge brainbox, Isaac Newton, who died when Emilie was 20. She did not just translate his writing from Latin to French; she also expressed Newton's obscure geometric proofs using the more accessible language of calculus. And she teased out of his convoluted web of theorems the crucial implications for the study of gravity and energy. That laid the foundation for the next century's discoveries in theoretical physics. The use of the square of the speed of light, c², in Einstein's most famous equation, E=mc² is directly traceable to her work.

Emilie's second piece of luck was that her father allowed her to use her brain: not much, admittedly, but certainly far more than most bright girls of her time and country. She was not sent to a convent. He was wealthy and liberal-minded enough to buy her books and talk to her about astronomy. He married her to Florent-Claude, Marquis du Châtelet-Lomont, who was a touch dull but decent—and unbothered by his brainy wife's intellectual and amorous adventures. Indeed, he liked and admired Voltaire.

Her third great good fortune was her array of mind-expanding, appreciative lovers. They may have been unsatisfactory mates by today's standards, but they were rarities in an age when few men looked for intellectual companionship from women. Emilie started by bedding the Duc de Richelieu, the “most sought-after man in France”. He bolstered her intellectual confidence, dented by an isolated childhood and early marriage. Even when she dumped him, they remained friends. Then came Voltaire, needy, self-indulgent, unreliable and self-centred—but still the love of her life and its great intellectual and cultural stimulus. Even when passion cooled, they remained great companions.

Finally, she fell in love with Jean-François, Marquis de Saint-Lambert, a much younger poet. He filled the emotional and physical gap left by Voltaire. But he also proved careless in what passed for contraception in those days. That led to pregnancy and the infection that killed Emilie when she was only 42.

It is tempting to speculate what heights of discovery Emilie might have achieved in a healthier and more open-minded age. But that would be to miss the point. The remarkable thing is that she managed so much, and with such good humour and reflective self-knowledge.

It is her biographer's good fortune that there is a great deal of accessible material about her life. Voltaire was spied on energetically; a thicket of secret police reports remains. So too do many of her letters, both sent and received.

The book may strike some readers as slightly lubricious in its attention to Emilie's sexual habits and predilections. A more serious shortcoming, explicable only by authorial laziness (unlikely) or publisher's stinginess (all too probable) is the startling and inconvenient lack of an index. That is just the sort of slap-happy approach to which Voltaire was prone, and which so pained Emilie.

Passionate Minds: The Great Enlightenment Love Affair.
By David Bodanis.
Little Brown; 312 pages; £17.99. To be published in America by Crown in October