Descartes, Meditations on First Philosophy, Part II

The deferential servant disappears immediately in the Preface to the Reader, and in its place are warnings against the hasty judgments of weaker intellects from a harried, misunderstood master. Descartes addresses two objections against his earlier work:

1. The human mind, when examining itself, does not find itself to be anything other than a thinking thing. But this does not necessitate that it is only a thinking thing
2. If a man conceives of an idea of a thing more perfect than himself, it does not follow either that the idea is more perfect than himself, or that the thing exists

Neither of these objections are resolved here. Descartes argues that objection 1 refers to the phenomenon of examining the mind, not an exhaustive definition; however, he will prove below that from this examination, it does in fact follow that the mind is only a thinking thing, and that nothing else belongs to the essence of the mind. Regarding objection 2, Descartes grants that ideas, taken as operations of the mind, cannot be greater than the mind, for an operation of the intellect, a part, is lesser than its cause, the whole. But taken as that which is represented by that operation, he will prove below how it follows that the more perfect thing really exists. 

He further cautions against hasty, careless study that does not bother to grasp the proper order of his arguments and the connections between them, and further, that readers should not pass judgment on the Meditations without reading his replies to the objections, a request I may or may not honor - since Descartes has already proven himself a liar, I don't really believe him that "it will be hard for anyone to think of any point of importance which these critics have not mentioned." It could certainly be true, but this sort of deference to a thinker isn't very reasonable, in any case. 

Curiously, after the Preface, Descartes writes a synopsis of the following six meditations. It will be useful to examine these synopses and compare them with the actual meditations - is his synopsis accurate? Does it add/omit anything important? 

1. The grounds for radical doubt, doubt carried to its extremes, so that it can form the basis of knowledge which we cannot doubt, i.e. that which is always and necessarily true - scientia or episteme. 
2. In doubting all things the mind becomes unaware that it cannot doubt its own existence, because doubt is a conscious activity. You cannot doubt that you are doubting, and a thing must exist in order to act.
3. The third meditation allegedly demonstrates the existence of God. Descartes acknowledges that while he thinks it's quite fully explained, "many obscurities may remain," a statement which is more than a little at odds with itself. 
4. The nature of knowledge as "that which we clearly and distinctly perceive." Isn't it a bit strange that the definition of knowledge comes after a demonstration for the existence of God? Further is discussed the nature of truth and falsity (but explicitly not sin, good, evil, nor anything regarding faith).
5. An account of corporeal nature and a new argument for the existence of God. All knowledge depends on the existence of God. Why would he prove again what he had already proved? 
6. Distinguishing the intellect from the imagination, the way in which the mind and the body make up a "kind of unit", and a presentation of arguments which enable the inference of material reality's being, while acknowledging material being is less certain than non-material being. 

Conspicuously absent is a meditation on the immortality of the soul, despite a) Descartes' claim that it, along with the existence of God, is the chief aim of this work, and b) God's existence being dealt with in not one but two meditations. In its place is a long digression in meditation 2's synopsis of what that argument requires:

1. Descartes' method is to lay out all the premises upon which a desired proposition depends, and this cannot be done in Meditation 2. 
2. A concept of the soul which is as clear as possible and quite distinct from every concept of body is the most important prerequisite for demonstrating immortality. This is done in Meditation 2.
3. The second prerequisite is knowing that "everything we clearly and distinctly understand is true in a way that exactly corresponds to our understanding of it". This is done in Meditation 4. 
4. The third prerequisite is a distinct concept of corporeal nature. This is partly done in Meditation 2, and partly in Meditations 5-6. 
5. All the things which we clearly and distinctly conceive as different substances are in fact truly distinct one from another. This is done in Meditation 6. 
6. Body being cannot be understood except as divisible; mind cannot be understood except as indivisible. 
7. The nature of mind and body are not only different but in some way opposite. 
8. This is enough to prove that the decay of the body does not imply the destruction of the mind

Descartes does not pursue this topic any further in Meditation 6. He asserts in the synopsis that concluding the soul is immortal depends on an account of the whole of physics, because we must understand that:

1. All substances are incorruptible and cannot cease to exist unless God withdraws his power from them.
2. Body, taken in the general sense, is a substance.
3. The human body, qua distinct from other bodies, is made up of accidents. 
4. The mind is not made up of accidents but is pure substance.
5. Even if the accidents of the mind change - different memories, desires, sensations - it is the same mind, whereas the body loses its identity if some of its parts change shape. 
6. Therefore, while the body can very easily perish, the mind is immortal by its very nature. 

This account has at least two problems: it is not clear and distinct, particularly premise 1 and how substance is "incorruptible." Therefore it does not have the quality of knowledge Descartes sets as the standard.  Second, premise 5 is false; for if my finger is amputated my body does not thereby lose its identity. Therefore the conclusion has not been demonstrated. The soul has not been proven immortal by its very nature.