Descartes' Two Accounts of Mind Body Union

First paragraph: Descartes was committed both to the Christian doctrine of the unity of man and to an experimentally oriented mechanistic science. Furthermore, he was committed to a dualistic metaphysics in which humans consist of a union of mind (res cogitans) and body (res extensa), which are absolutely distinct substances. There has been little agreement on how his explanation of union reflects his commitments. Some philosophers argue that Descarte's primary or only account of union was the "co-extension" view because it is compatible with the unity of man. As we will see, however, the co-extension account would not have satisfied Descartes' scientific inclinations. Philosophers who pay serious attention to the difficulties with the co-extension account argue that Descartes accepted or should have accepted the "natural institution" account of union, which is compatible with his scientific commitments. However, the natural institution account is guilty of a Platonism and arbitrariness that conflicts with the unity of man. I will argue that Descartes' desire to accommodate all his commitments drove him to accept and be devoted to both the co-extension and the natural institution accounts.