Dualists hold that the human person consists of both a soul (or mind) and a body. For healthy, fully-functioning human beings, the person is a unified subject, but at times such as physical death, dualists hold that persons (souls or minds) can survive the destruction of their bodies.
According to the Catechism of the Catholic Church: "The Church teaches that every spiritual soul is created immediately by God--it is not 'produced' by the parents--and also that it is immortal: it does not perish when it separates from the body at death, and it will be reunited with the body at the final Resurrection." In his address to the Pontifical Academy of Sciences in 1996, Pope John Paul II said, "It is by virtue of his spiritual soul that the whole person possesses such a dignity even in his body. Plus XII stressed this essential point: if the human body takes its origin from pre-existent living matter, the spiritual soul is immediately created by God."
St. Thomas Aquinas is sometimes described as opposing dualism. Indeed, as a follower of Aristotle he at times is readily thought of as claiming that the soul is the mere form of the body. But for St. Thomas the soul is no mere form as in shape; it is a subsistent being, requiring a special creation by God and capable of existing independently of the human animal body. In Summa Contra Gentiles, St. Thomas writes: "Now, it pertains to the human soul distinctively, in contrast to other forms, to be subsisting in its being.... But since the human soul does not have matter as part of itself, it cannot be made from something as from matter. It therefore remains that the soul is made from nothing. And thus, it ... is created immediately by God alone."
Regrettably, the term "dualism" today has become encrusted with assumptions that denigrate the body, such as the view that the body is a mere tool or instrument or, worse, that the body is some kind of prison that has entrapped our souls. Of course, there can be times of severe damage when the mind-body relationship is fractured, as with prosopagnosia (when a person can lose the ability to recognize other humans by their faces despite having good eye sight) or when physical damage causes one to experience "phantom limbs." But dualists today (who include many scientists and philosophers) recognize the radical interdependence of mind and body.
In "Dualistic Delusions" (February), Patrick Lee and Robert P. George rightly note that the denial of dualism, materialism, is not established by the fact that physical damage causes psychological damage. In fact, the practice of the medical sciences seems to assume the causal interaction between the physical and the mental. If one were to restrict...