Howard Fischer
Uppsala, Sweden

René Descartes (1596–1650) was a French philosopher, mathematician, and scientist. He obtained a law degree in 1616 at his father’s insistence, but in 1618 became an officer in the army of the Dutch Protestant States. He is thought to have influenced the work of Isaac Newton and also created the foundations of calculus. By 1649, he was one of Europe’s best-known philosophers and scientists, and had lived in the Netherlands—as a heretical Catholic—for about twenty years. Despite his renown, he lived in near poverty.¹

A few years earlier, Pierre Chanut (1601–1662), the French ambassador to Sweden, met Descartes and started to correspond with him. Chanut showed some of Descartes’ writings to Queen Christina of Sweden² (1626–1689), and she also began writing to Descartes. Christina had succeeded her father, King Gustavus Adolphus of Sweden, after his death in 1632. A regent ruled Sweden for the young Christina, who was finally crowned at age eighteen in 1644. She became “one of the most learned women of the seventeenth-century,” interested in philosophy, religion, mathematics, and alchemy. She spoke Swedish, Danish, Dutch, German, French, Italian, Arabic, and Hebrew, was visited by European scholars, and collected books and rare manuscripts. She invited opera and ballet companies to Stockholm.

In 1649, Christina invited Descartes to Sweden, and he accepted after she asked him to organize a scientific academy. She sent a ship that transported him and 2,000 of his books to Sweden. Descartes arrived in October 1649, and moved in with his friend, the French ambassador Chanut. There he had “all the comforts of French culture in a very rude and semi-civilized society.”³

His philosophy lessons with Queen Christina started in December 1649. She had him come to the castle, only about 500 meters from the French embassy, at 5 AM. Descartes and Christina did not like each other. By mid-January 1650, he had only seen the queen four or five times. On the first of February, 1650, Ambassador Chanut began to have a respiratory illness, which later progressed to pneumonia. Descartes became ill the next day. He died on February 11, 1650.⁴ His death was attributed to pneumonia with the possibility of an associated pleurisy (inflammation of the membrane lining the lungs and the chest cavity). Chanut, however, recovered. It has been repeated through centuries that the cold northern climate, the drafty castle, and the early awakenings contributed to Descartes catching Chanut’s pneumonia.⁵

In the 1980s, letters⁶ surfaced, including one from Dr. Jan van Wullen, a Dutch physician in Stockholm, who had been sent by Queen Christina to treat Descartes. He wrote that Descartes had increased skin pigmentation and hematuria (blood in the urine). These are not typical findings in patients with pneumonia, although Descartes’ vomiting, diarrhea, and abdominal pain were.⁷ Could there be another explanation for the savant’s death? After the van Wullen letter was discovered, it was suggested that Descartes was poisoned, perhaps by a Protestant clergyman, to prevent Descartes’ convincing the queen to convert to Catholicism,⁸ a move she had long been considering.

Theodor Ebert at the University of Erlangen, Germany thinks that Descartes was poisoned with arsenic.^9,10 Acute¹¹ arsenic poisoning—less than 0.1 gram may be fatal¹²—will produce vomiting, diarrhea, abdominal pain, heart failure, seizures, coma, and death. Chronic arsenic poisoning will produce the same conditions that acute poisoning will, but also produces thickening and hyperpigmentation of the skin. The hyperpigmentation is classically described as looking like “raindrops have fallen on a dusty road.”¹³

Critics of Ebert’s arsenic theory ask if Dr. van Wullen could tell hematuria from the dark, concentrated urine seen in febrile, dehydrated patients. Ebert¹⁴ dismisses this question. Critics also maintain that Descartes had influenza with a superimposed bacterial infection. Ebert suggests that Descartes was poisoned by arsenic-laced communion wafers administered by Father François Viogué, a Catholic priest attached to—and living in—the French embassy. The motive for the poisoning, according to Ebert, was that Descartes was instructing Queen Christina in a heretical sort of Catholicism, one in which transubstantiation (the transformation of the host into the body of Christ) did not occur.¹⁵ For believers, transubstantiation was a dogma not to be questioned.

Descartes, however, only received communion twice from Viogué, and his symptoms are much more compatible with chronic arsenic poisoning. Also, the desecration of the communion host by a Catholic priest in order to murder someone would be a horrible crime within the Church.¹⁶

As for the hematuria, chronic low-dose arsenic ingestion (in drinking water) may produce hematuria, but the duration of exposure required is not known.¹⁷ Fever, however, may also cause hematuria.¹⁸

If only we had a lock of Descartes’ hair to test for arsenic.

References

1. “René Descartes.” Wikipedia.
2. “Christina, Queen of Sweden.” Wikipedia.
3. John Mahaffy. Descartes. Edinburgh: William Blackwood and Sons, 1880.
4. “René Descartes,” Wikipedia.
5. Bess Lovejoy. Rest in Pieces. Richmond, UK: Duckworth Books, Ltd, 2021.
6. Philosopher Ad Absurdum. “Descartes’ death: Descartes was murdered…or was he?” September 12, 2021. https://philosopheradabsurdum.com/2021/09/12/descartes-was-murdered-or-was-he-the-death-of-rene-descartes-odd-histories/
7. Antonio Correras. “Why did Descartes die?” Lite Strabo, April 22, 2007. https://litestraboen.blogspot.com/2007/04/why-did-descartes-die.html
8. Philosopher Ad Absurdum, “Descartes’ death.”
9. Joe Carter. “Was Descartes poisoned by a Catholic priest?” First Things, February 15, 2010. https://www.firstthings.com/blogs/firstthoughts/2010/02/was-descartes-poisoned-by-a-catholic-priest
10. Theodor Ebert. “La maladie mortelle de Descartes – pneumonie ou empoisonnment?” PhilPapers, 2015. https://philarchive.org/archive/EBELMM
11. “Arsenic poisoning.” Wikipedia.
12. “Arsenic trioxide.” Wikipedia.
13. Kim Gehle. “Arsenic toxicity: What are the physiologic effects of arsenic exposure,” Environmental Medicine, May 19, 2023.
14. Vincent Carraud and Renaud Verdon. “Remarques circonspectes sur la mort de Descartes.” Dix-Septième Siècle, 256, 2014.
15. André Fabre. “René Descartes in Sweden.” Histoire et Médecine, November 2010. web.archive.org
16. Bill Vallicella. “Was Descartes poisoned by a Catholic priest?” Maverick Philosopher, February 15, 2010. https://maverickphilosopher.typepad.com/maverick_philosopher/2010/02/was-descartes-poisoned-by-a-catholic-priest.html
17. Tyler McClintock et al. “Association between arsenic exposure from drinking water and hematuria: Results from the Health Effects of Arsenic Longitudinal Study.” Toxicology and Applied Pharmacology, 276(1), 2014.
18. Mark Perazella and Michael O’Leary. “Etiology and evaluation of hematuria in adults.” Up To Date, November 2023.