For centuries, people thought Descartes—the father of modern philosophy ("the simple meaning of the phrase [cogito ergo sum] is that if one is skeptical of existence, that is in and of itself proof that he does exist")—died of pneumonia.

... or was it muuuuurder?

According to Theodor Ebert, an academic at the University of Erlangen, Descartes died not through natural causes but from an arsenic-laced communion wafer given to him by a Catholic priest.

Ebert believes that Jacques Viogué, a missionary working in Stockholm, administered the poison because he feared Descartes's radical theological ideas would derail an expected conversion to Catholicism by the monarch of protestant Sweden. "Viogué knew of Queen Christina's Catholic tendencies. It is very likely that he saw in Descartes an obstacle to the Queen's conversion to the Catholic faith," Ebert told Le Nouvel Observateur newspaper.

How much do you want to bet that Dan Brown furiously re-reading the Discourse on Method as you read this post?