Don't Walk Away, René

iii.

     In the Third Meditation Descartes formalizes the theory that whatever he perceives clearly and distinctly is true.  He knows he is a thinking thing because he cannot doubt himself in the act of inquiring; i.e., he perceives, clearly and distinctly, his own nature as that which inquires.  What prevents him from being certain about the existence of bodies is that he perceives the ideas of bodies only, beyond which he cannot see.  

     He takes up some of the terminology of Scholastic philosophy, along with some of its assumptions about the nature of reality, in order to get beyond the confines his original argument had set up against further progress.  Having established his identity as a thinking thing, he situates this identity in a system of identities, presumably, based on my limited research, inherited from medieval Christian philosophy, but possibly ultimately derived from Aristotle (?):  reality is composed of substances, which exist concretely in their own right, of which bodies and minds are two kinds; substances have attributes, or qualities: some essential or primary and some accidental or secondary; these attributes in turn have modes, or ways they can modify substances.  Extension is the primary, essential attribute of bodies, because this is what makes them bodies; and figure is a mode of extension.  Differently shaped bodies are all extended but distinguishable from each other by their respective figures, and so on.  Minds, being thinking things, have the essential attribute of thought; and in the course of doubting, understanding, willing, etc. manifest the various  modes of thought.

     Thoughts cannot exist without minds, and so, in Descartes' terminology, have less reality than minds, just as a mode of extension has less reality than an extended thing, which exists in its own right.  A shape has less reality than a thing with some particular shape, because it exists only in the existence of the thing; and roundness has even less reality than shape, because there must first be such a thing as shape in general before there can be, among its possibilities, one called roundness; while the reverse is not true--shape as such does not depend upon the existence of roundness as one of its modes.  

     Descartes remarks that, although all his thoughts are in one sense the same, they are in another very different:  they share the same "formal" reality as modifications of the attribute of thought; but, in that they are about different kinds of things, they have different "objective" realities.  Some represent substances, some attributes, some modes; and in this they have different degrees of objective reality.  A substance is more real than its attributes because it must exist to support them; it brings them into being.  Since our ideas of bodies--i.e., our sensible images of them--are among the effects produced by them (he assumes), it follows that the bodies themselves have more reality.

     He reasons that, in all cases, a cause has at least as much reality as its effects.  Moreover, the original cause of an idea must have at least as much formal reality as the idea has objective reality, though it may act through a series of ideas.  The idea of a rock must have originally been caused by a rock or by something with as much formal reality, and not, e.g., by a mode of extension. 

     God, then, according to Descartes, is the infinite mind.  Because, in Scholastic terms, infinite substances have more reality than finite ones, it is not possible that our idea of God has as its ultimate cause a mere finite substance or another idea.  Because Descartes can conceive of a thing whose cause must be something with more formal reality than he himself possesses, he knows (he supposes) that there is something outside himself.  And because he can conceive of the infinite mind, he knows (he supposes) that the infinite mind exists, because no finite substance could have been its original source.  So God exists and he, Descartes, is not God.  

     

     It seems to me that, in his Third Meditation, Descartes has largely abandoned the project begun in the first two Meditations.  Rather than proceed by continuing to doubt wherever possible in order to isolate possible foundations of knowledge, he has escaped from the grave limitations he had imposed on himself by appealing to a tradition, with little argument.  I will briefly enumerate my objections to the "progress" achieved in the Third Meditation: (1) he defined God as the infinite mind, elaborating a series of questionable perfections for him, and had already prepared a place for him in his metaphysics, to which he ascended without argument.  It isn't clear to me that there can be an infinite mind.  I would submit that there's nothing clear or distinct about God as he describes him with his various moral and other superlatives; (2) even if there is a logical hierarchy of dependence, such that modes depend on attributes which depend on substances, it does not follow that ideas of substances depend on (real) substances.  There is no obvious reason to suppose that the causes of ideas must possess as much formal reality as the resulting ideas possess objective reality; this is something that can be doubted and for which Descartes has not argued; (3) even if God exists, there is no ground for assuming that deception is  a sign of imperfection, and no reason to exclude it as a possibility. 

     I'm not sure I extracted everything from this Meditation I should have.  Let us see what my friend Dr. Muad'dib Kenobi Seagull has to say about it.