Mon cher ange,Écrasez l'infâme.À Ferney, ce 12 maiJe vous embrasse de tout mon cœur.Il faut cultiver notre jardin.Sire, votre majesté…Madame, je reçois votre lettre…Mon cher Thieriot,Mon cher ange,Écrasez l'infâme.À Ferney, ce 12 maiJe vous embrasse de tout mon cœur.Il faut cultiver notre jardin.Sire, votre majesté…Madame, je reçois votre lettre…Mon cher Thieriot,Mon cher ange,Écrasez l'infâme.À Ferney, ce 12 maiJe vous embrasse de tout mon cœur.Il faut cultiver notre jardin.Sire, votre majesté…Madame, je reçois votre lettre…Mon cher Thieriot,Mon cher ange,Écrasez l'infâme.À Ferney, ce 12 maiJe vous embrasse de tout mon cœur.Il faut cultiver notre jardin.Sire, votre majesté…Madame, je reçois votre lettre…Mon cher Thieriot,Mon cher ange,Écrasez l'infâme.À Ferney, ce 12 maiJe vous embrasse de tout mon cœur.Il faut cultiver notre jardin.Sire, votre majesté…Madame, je reçois votre lettre…Mon cher Thieriot,
Estimated · Cox, 1926 · no test existed

Voltaire's IQ

Two spells in the Bastille, two exiles, some 2,000 books and pamphlets and 20,000 surviving letters. François-Marie Arouet wrote his way out of every cell they put him in.

≈190
Cox's adult-corrected estimate
20,000
Surviving letters · 51 volumes

Voltaire never took an IQ test. The ≈190 is Catharine Cox's 1926 estimate, helped by his unusually well-documented Jesuit schooling at the Collège Louis-le-Grand — a retrospective inference, not a measurement.

84 years, mostly away from Paris

Prison, exile and refuge shaped almost everything he wrote. Tap a stretch of his life.

16941778
1758–1778
Ferney

Twenty years running his own small estate: watchmaking, silk, housing for refugees, 200+ letters a month — and Candide.

Education, in sealed letters

He wrote more than 20,000 letters. Here his schooling is told as a short correspondence — from the Jesuits who trained him to the law career he refused.

1704–11
Collège Louis-le-Grand, Paris

Seven years with the Jesuits: Latin, Greek, rhetoric and theatre. He learned to argue — and to distrust the Church that taught him.

1704–11
Friendships at school

Classmates included the d'Argenson brothers, later ministers who protected him for decades.

1700s
Abbé de Châteauneuf

His freethinking godfather introduced him to the libertine Société du Temple while still a boy.

1711–13
Law, Paris

Enrolled to please his father, a notary; he spent the time writing verse instead.

1713–14
Embassy in The Hague, then a notary's office

Sent as a secretary to the French ambassador, recalled over a love affair, then placed as a law clerk — the last attempt to make him a lawyer.

1726–1734

England, and a book they burned

After a quarrel with the Chevalier de Rohan-Chabot — insult, retort, a beating by hired men, a challenge to a duel — the Rohans had him locked up again, then exiled. In England he met constitutional monarchy, religious toleration, Newton and Locke, and learned English well enough to read them.

His Lettres philosophiques (1734) compared English and French institutions — a thin disguise for an attack on absolutism. The Paris parlement had it burned. He fled to Cirey.

Cirey, 1734–1749
With Émilie du Châtelet

His most scientific years were spent with Émilie du Châtelet, a mathematician and physicist more rigorous than he was. Together they worked on Newtonian physics; her French translation of Newton's Principia, with commentary, is still the standard one. Voltaire also wrote the Essay on the Customs and Spirit of Nations, a pioneering comparative history.

Ferney · the Calas affair

Three years to clear a dead man's name

Jean Calas, a Protestant in Toulouse, was executed in 1762 for the murder of a son who had in fact taken his own life. From Ferney, Voltaire investigated, published and rallied opinion until the verdict fell. The campaign made him Europe's leading voice for toleration.

1762Jean Calas executed in Toulouse.
1762Voltaire takes up the case from Ferney.
1763Treatise on Tolerance.
1765Calas exonerated by royal command.

Similar campaigns followed for the Sirven family and the Chevalier de la Barre. The Treatise on Tolerance (1763) and the pocket-sized Dictionnaire philosophique (1764), designed to be passed hand to hand, became founding texts of European secularism. Candide (1759) came from the same desk.

Two thousand works, six genres

His collected works run to about 200 volumes. Beyond the books already covered above, these are the landmarks of each genre.

Tragedies50+ plays
1732
Zaïre — his greatest stage success
1741
Mahomet — a thinly veiled attack on fanaticism
1743
Mérope — praised as his most perfect tragedy
Epic poetry2 epics
1723
La Henriade — Henri IV and religious war
1755
La Pucelle d'Orléans — a scandalous mock-epic of Joan of Arc
Historypioneer
1731
Histoire de Charles XII — the Swedish warrior-king
1751
Le Siècle de Louis XIV — history of a whole civilisation, not just its wars
Philosophical tales26 contes
1747
Zadig — fate and reason in an imagined Babylon
1752
Micromégas — a giant from Sirius visits Earth — early science fiction
1759
Candide — “We must cultivate our garden”
1767
L'Ingénu — a Huron in France
Sciencepopular physics
1738
Éléments de la philosophie de Newton — brought Newton to French readers
Poems & letters20,000+ letters
1756
Poème sur le désastre de Lisbonne — the earthquake as a challenge to optimism
1760s
“Écrasez l'infâme” — the slogan signing off his letters against intolerance

Did Voltaire actually say it?

Few writers are misquoted as often. Tap a card for the verdict.

1778
Return and death

Back in Paris after 28 years for his last play, Irène, he was cheered at the Académie. He died on May 30, aged 83, and was refused burial in consecrated ground in Paris.

1791
The Panthéon

After the Revolution his remains were brought back to Paris and placed in the Panthéon.

Timeline

1694Born François-Marie Arouet in Paris.
1718Takes the pen name Voltaire.
1746Elected to the Académie française.
1753Detained in Frankfurt by Frederick the Great's agents.
1758Buys the Ferney estate near Geneva.
1778Dies in Paris, May 30.

Reading the ≈190

Cox's method rewards the kind of structured childhood evidence a Jesuit school produces, and underrates people with thinner records. Read the figure as a historical artifact.

Sources

  1. Cox, C. M. (1926). The Early Mental Traits of Three Hundred Geniuses
  2. Voltaire (1759). Candide
  3. Voltaire (1764). Dictionnaire philosophique
  4. Voltaire (1763). Traité sur la tolérance
  5. Pomeau, R. (1985–1994). Voltaire en son temps
  6. Besterman, T. (ed.) — Voltaire correspondence (51 vols.)
  7. Hall, E. B. (1906). The Friends of Voltaire
  8. Mason, H. (1981). Voltaire: A Biography. Granada

Other Cox-era estimates

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