A new book by the german philosopher Theodor Ebert makes the claim that “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.
Read more here.