https://www.bu.edu/wcp/Papers/Onto/OntoDerk.htm

“Conway’s Criticisms of Cartesian Dualism.

Conway presents a total of six arguments for what she calls the convertibility of matter and spirit. By this she means that matter and spirit are not totally different substances but are able to change into each other. Material entities can become spiritual entities and vice versa. In the course of these arguments, she presents arguments against dualism since dualism denies the possibility of convertibility. Since her arguments are very extensive, I will only discuss a few of the points she makes against dualism in her third and fourth arguments.

The first point I would like to discuss is found in Conway’s third argument against dualism. (8) Conway here argues that dualists are inconsistent. On the one hand, they seem to be making absolute distinctions between body and soul and on the other hand they seem to admit that body and soul must have certain characteristics in common.

Dualists are inconsistent because they distinguish sharply between body and spirit, that is, the penetrable and the impenetrable, the extended and non-extended, the locatable and non-locatable, the divisible and the non-divisible, the figurable and the non-figurable, but they smuggle in concepts to describe the spritual substance which in fact are not as dualistic as they claim. Spirit, according to dualists, can in fact be attributed “extension, mobility and figurability”, (to quote Conway) all attributes of penetrable bodies. For example, even dualists speak of spirit as locatable somewhere, perhaps in the sense that a person’s spirit is seen as residing in the same location as his body because such a location allows a spirit to experience that which is happening inside and in the area around the body). Spirit is also seen as something which can move, for example, one can imagine oneself being in another place, an example which Descartes himself uses. It is also seen as having figurability, in other words, it is characterised in certain ways or even perhaps seen to have a physical form such as the form of an aura or ghost. Spirit is thus seen by dualists as having extension and divisibility, as locatable and moveable. But, if this is the case, Conway says, then surely spirit must also be penetrable, that is, it must be seen as sharing in the essential characteristics of matter. Conway wonders why “…the Extension of Body and Spirit, as they [dualists] understand it, do wonderfully differ…”

In Conway’s fourth argument, she argues that Descartes, in separating matter and spirit, has a view of the bodies as dead or lifeless, as not containing spirit. Conway objects to this that since all things can in principle change into all other things and that hence the animate comes forth from the inanimate, one cannot separate reality into spiritless, lifeless matter on the one hand and non-material spirit on the other.

As to the body of an animate creature, in Descartes’ view, it is a machine which moves itself. But such a body, because it is solely made up of matter is lifeless, Conway argues. This is because, for Descartes, even though the body is moved by animal spirits, the material from out of which it is made does not contain anything spiritual.

Conway’s critique of Descartes’ view of the body as “dead matter” must be seen in the context of the 17th century discussion of Aristotelian vitalism versus Cartesian mechanism. The vitalists regarded the soul as the form of the body, making it that particular body and as the source of the vital functions of the body, that is, the vegetative, sensitive and rational functions. The mechanists thought that all the vital functions of the body could ultimately be explained through the laws of physics, the ultimate science of the material world. Descartes believed that the body of animals was a machine whose functions could be fully explained in a mechanical way and that of humans as a similar type of machine, except that it is also the bearer of an eternal soul.”