The Ghost and the Princess

The correspondence of René Descartes and Princess Elisabeth of Bohemia — a debate about mind, soul, and immortality

‘Aristotle with a Bust of Homer’ (detail) by Rembrandt van Rijn, 1653, via the Metropolitan Museum of Art, purchase, special contributions and funds given or bequeathed by friends of the Museum, 1961

There is an “official theory” about the nature of minds that “hails chiefly from Descartes,” wrote Gilbert Ryle, an Oxford philosopher. According to the theory, each person has a…