Descartes' dualism of mind and body is a lasting legacy. Nowadays many people still believe the body is less well-known than the mind and that there is a mystery about how the mental and the physical can interact. His correspondence with Princess Elizabeth of Bohemia prompted him, late in life, to explore the union of mind and body in his last work, The Passions of the Soul. In retrospect, Descartes seems to have had two views of how mind and body might be related, one that the mind interacts with the body via a gland in the brain, the other that mind is spread all the way through body and intermingled with it. While neither view is satisfactory, it is still not clear nowadays how best to think about the relation of the mental to the physical. Copyright 2014 La Trobe University, all rights reserved. Please contact for permissions.