Copyright @ 1999 by Gerald J. Massey


Dedication and Preface to the Meditations on First Philosophy

Dedication to the theology faculty at the University of Paris:

Descartes implores the Dean and the Faculty of Sacred Theology at the University of Paris (the Sorbonne) to put their authority and prestige behind his Meditations on First Philosophy, thereby recommending his work to others as religiously orthodox and philosophically solid. Doubtless, Descartes also hoped that their support would insulate him against any possible charges of heresy or impiety. [Their endorsement was never given!]

Descartes believes that the questions of the existence of God and of the immortality of the soul belong to so-called natural theology, i.e., to that part of philosophy that deals with such ultimate questions.

Descartes thinks that it is easier to know that God exists than it is to know material things, and that we have greater certitude about the former than about the latter. Descartes maintains that both the bible and traditional Catholic teaching support his position. Moreover, he thinks that we do not even have to go outside our own minds in order to arrive at certain knowledge of the existence and attributes of God.

Descartes also thinks that it is easy for us to come to know that the soul is distinct from the body, a position officially endorsed by the Lateran Council of 1513, which also taught that the proposition that the soul does not die with the body can be established in natural theology.

Disavowing novelty for his own proofs, Descartes claims that virtually all the proofs that have throughout history been advanced by major thinkers for the existence of God and for the distinctness of the soul from the body possess, when properly understood, the force of demonstrations. For himself, Descartes claims only to have taken the principal and most important arguments for these two truths and to have cast them into the form of demonstrations so evident and certain that no unbiased, rational person could deny their cogency. Nevertheless, Descartes doesn't expect everyone to understand and accept his proofs. Descartes notes that relatively few persons are able to understand and evaluate proofs or demonstrations in geometry because of their great length and complex interrelations. He believes that even fewer persons are able to understand and evaluate philosophical proofs or demonstrations for God's existence and for the distinctness of soul and body, because these proofs or demonstrations are not only lengthy and interrelated in complex ways but also because they can be grasped only by a mind that is unbiased and detached from the senses.

Descartes hopes that, by becoming advocates of his work, the University of Paris theology faculty will (a) cause any errors in it to be corrected, (b) cause defective passages to be clarified and improved, and (c) publicly endorse as bonafide demonstrations his proofs of God's existence and of the real distinction of the soul from the body, thereby once and for all eradicating from the human mind all errors on these two heads.

Descartes's Preface to the Reader:

The Discourse on Method was an exoteric (popular) work written in French for educated persons with robust common sense. It did not purport to be a full exposition of Descartes's philosophical thinking, but only a condensed sketch. By contrast, the Meditations on First Philosophy is an esoteric (scholarly) work written in Latin for philosophical and theological specialists.

Since its publication in 1637, Descartes says he has received only two objections to material in the Discourse on Method that deserve to be taken seriously. The first objection maintains that the inference from the premiss that the mind perceives itself to be only a thinking thing to the conclusion that the whole nature or essence of the mind is to think is an invalid inference. By way of rejoinder, Descartes says that what he had meant to say in the Discourse on Method was that the only thing he was aware of as belonging to his nature or essence was that he was a thinking thing, and not that his whole nature in fact was a thinking thing. Nevertheless, he claims that the conclusion does follow logically from the premiss, but that showing this requires argument that he will now supply in the Meditations.

The second objection holds that the inference from the premiss that I have within me an idea of something more perfect than myself to the conclusion that this idea is more perfect than I am, as well as the inference from the aforesaid premiss to the conclusion that the thing denoted by this idea exists, are invalid inferences. Descartes replies that the term idea is ambiguous: taken materially, it is an operation of the intellect; taken objectively, it is the thing represented by that operation of the intellect. Taken materially, the idea of a thing more perfect than myself is clearly not more perfect than I am. But taken objectively, the idea of a thing more perfect than myself can be, by virtue of its nature or essence, more perfect than I am. Again, the inferences from the premiss to the two conclusions are valid but have to be shown so by arguments that Descartes will supply in the Meditations.

Descartes urges that people read his Meditations only if they are able and willing (a) to meditate along with him, and (b) to withdraw their minds from their senses and from all preconceived opinions. So many talented and learned minds have sent him comments and objections that Descartes thinks it unlikely that anyone will come up with any new comments or objections of substance.

Descartes considers the seven sets of Objections & Replies that he appends to the Meditations to form an integral part of this work. He asks his readers to suspend judgment on the work until they have read carefully through these objections and his replies to them.



Gerald J. Massey


[Descartes's Meditations on First Philosophy is generally hailed as one of the most important philosophical tracts ever written. Superficially, it appears easy to understand, but it is in fact a deep essay. As you work your way through it, keep the Study Guide questions in mind. You might find it helpful to write out, at least in sketchy form, answers to these Study Guide questions. Then, once you have heard Professor Massey's lectures on the relevant part of the Meditations and discussed it in recitation section, you should revise and amplify your preliminary answers. If you proceed this way, you'll undoubtedly get a lot out of the course, you'll enjoy it, and you'll likely do very well in it.]

Dedication to the theology faculty at the University of Paris:

Why does Descartes address these people? What is he trying to protect himself against? What does he hope these people will do for him?

Does Descartes think that the questions of the existence of God and the immortality of the soul belong to theology or to philosophy?

Does he think that it is easy to know that God exists? Does the bible support his view? Does the Catholic Church support it?

Does Descartes think that we must go outside our own minds in order to arrive at the existence of God?

Does he think that it is easy to come to know that the soul is distinct from the body? What does the Catholic Church teach on this head?

Does Descartes think that anyone has advanced cogent proofs of God's existence and of the distinctness of the soul from the body? What novelty does he claim for his proofs?

Does he expect everyone to understand and accept his proofs? Why not? What kind of mind is required to grasp them? Why does he try to enlist the University of Paris theology faculty as advocates of his proofs?

Descartes's Preface to the Reader:

In what sense is the Discourse on Method an exoteric (popular) work whereas the Meditations on First Philosophy is an esoteric (scholarly) work for the philosophically initiated? In what languages were they originally written?

What are the two objections to the Discourse on Method that Descartes thinks are worthy of being taken seriously? How does he answer them at this stage?

What demands does Descartes put on his readers? Does he expect them to come up with novel and interesting objections to his arguments? Did he expect the University of Paris theology faculty to come up with such objections?

Does he think that the Objections & Replies that he appends to his six meditations form an integral part of this work? If so, why do English editions of the Meditations on First Philosophy often omit them?

Descartes's Synopsis of the six meditations:

Before you read each mediation, read carefully Descartes's own synopsis of it. His synopsis will help you to focus on the most important points. If in a meditation you find some important matter that is not mentioned in his synopsis, make a note of it and try to explain its omission.

Nowhere in the six meditations does Descartes claim to prove that the soul is immortal, but only that it is distinct from the body. Yet, in his synopsis of the second meditation, Descartes sketches a proof of the soul's immortality that turns on the principle that substances are by nature incorruptible. Try to reconstruct and flesh out this proof. Once you've read all six meditations, try to explain why Descartes did not include this proof in any of them.

What is the principal goal or object of the Meditations? Hint: Look closely at Descartes's synopsis of the sixth meditation.

First Meditation: Concerning those things that can be called into doubt:

Why does Descartes reject the doubtful in the way that most thinkers would reject the false? How doubtful must something be for him to reject it?

How does Descartes bypass the endless task of inspecting each of his beliefs in order to ascertain whether it is in any degree doubtful? On what does he think all his beliefs depend in such a way that, if he can discredit it, he will have thereby succeeded in discrediting all his beliefs?

What is the first way in which Descartes discredits beliefs based on the senses?

Only lunatics doubt that they have hands and feet, that they are moving about, and similar beliefs based on the senses. Descartes is assuredly no lunatic, so how does he propose to discredit beliefs such as these?

Does Descartes think we can tell whether we are asleep or awake? Why not?

Even if we're actually dreaming when we think we're awake, doesn't it follow that the elements out of which our dreams are made or composed really exists? Doesn't it at least follow that the very general features of our dreams -- things like (spatial) extension, number, place, and time -- really exist? Don't the sciences that deal with these things -- arithmetic and geometry -- give us infallible knowledge of them?

How does Descartes appeal to God's existence to render doubtful the propositions of mathematics? Could a perfectly good God really will to deceive us all the time? Once in a while? Ever?

If we are either uncreated or created by a less than perfectly good God, Descartes thinks that the propositions of mathematics are doubtful. Why?

What is the point of the Evil Demon hypothesis? Can the Evil Demon deceive me if I refuse to assent to whatever is in any way doubtful?

Second Meditation: Concerning the nature of the human mind; that the mind is more known than the body:

What, at the beginning of this meditation, does Descartes deem to be doubtful? (Remember, the Evil Demon hypothesis remains in force.)

What is the one thing that the Evil Demon could not possibly deceive me about? What follows immediately from this about my existence?

Having established beyond any doubt that he exists (at least so long as he is thinking), Descartes asks what kind of thing he is, i.e., what is his nature. Why does he view "a human being" and "a rational animal" as bad answers to this good question?

Why does Descartes think that having a body and doing things that necessarily involve the body, e.g., walking, are not part of his nature, of what he is essentially? In what way does he invoke the Evil Demon to make these points?

What does Descartes take a thing that thinks to be? Are doubting, willing, seeing, and smelling all ways of thinking for Descartes? Does he distinguish between seeing and seeming to see, or between smelling and seeming to smell? Why not?

Could I really be a body even though so far as I can tell I am only a thinking thing? That is, might not a body and a thinking thing really be one and the same?

How does Descartes use the piece of wax example to show that the soul (the mind) is better and more distinctly known than the body? What is the point of the story about looking down at men wearing hats and coats in the street? Does the observer literally see the men? In what way does everything we learn about the body teach us something more fundamental about the mind?

Third Meditation: Of God, that He exists:

Descartes takes himself to be a thing that thinks. What exactly is such a thing? What does Descartes mean by thinking? Are doubting, willing, feeling pain, and smelling all examples of thinking?

Descartes is certain that he exists and that he is a thinking thing. What is the ground of this certitude? How does he infer from this ground the general principle or rule that anything we clearly and distinctly perceive is true? Is this a good inference, i.e., a valid inference?

Don't we clearly and distinctly perceive an external world? What does Descartes say about this?

Don't we clearly and distinctly perceive many mathematical facts, e.g., that 3 + 2 = 5, or that a square has four sides, or that a surface must have two sides? Could an omnipotent God deceive me about such matters? Could He deceive me about the Cogito? How serious is the doubt that turns on this consideration? Why does Descartes call this doubt metaphysical? Why does he think that it is imperative to eliminate this metaphysical doubt? What must he establish in order to eliminate it?

Descartes divides thoughts into ideas, emotions, volitions, and judgments. What, in this context, does he mean by ideas? Which of these thoughts can properly be said to be false? In what special sense are ideas sometimes said to be false? What is the chief and most common mistake people make with respect to their ideas?

I seem to get my ideas in three ways: (a) from external things acting on me; (b) innately from within; and (c) from my own mental activities and constructions. Why do I tend to think that ideas of the first kind (a) are similar to objects in the external world? Is my inference to these objects cogent?

Descartes says that nature teaches him that, for many of his ideas, there are things in the external world that are similar to them. He distinguishes nature in this context from nature in the expressions "the light of nature" or "the natural light." Explain these two different senses of the word "nature." What does Descartes mean by the light of nature or the natural light? What is its use or function? Mention several things that Descartes thinks he knows by means of the natural light or the light of nature. Are the deliverances of the natural light doubtful in any degree? Why not?

If an external object causes an idea in me, must the latter resemble the former? What is the moral or lesson of Descartes's account of his two ideas of the sun?

Having failed to establish the external world by means of inferences that take off from ideas of ostensible external objects, Descartes now tries a completely different tack to accomplish the same thing. Describe this new tack.


1.  Qua modes of thought, all Descartes's ideas are ontologically on a par, i.e., they all have the same low degree of formal reality.  Their formal reality is even less than the formal reality of finite, inanimate, corporeal substances (if there be any such substances!).

2.  Qua what his ideas represent, Descartes notes that his ideas can and do differ markedly, some having much more -- or much less -- objective reality than others.  E.g., his idea of God as perfect, supreme, eternal, infinite, omniscient, omnipotent, and creator of everything besides himself has more objective reality than his idea of finite substance has.

3.  The natural light reveals to Descartes causal principle (C1), to wit: there must be at least as much reality or perfection in the total efficient cause as there is in any of its effects.
(a)  The reality or perfection of the effect can exist either formally or eminently
      in its cause;
(b)  C1 applies both to formal reality and to objective reality.

4.  The natural light also reveals causal principle (C2) to Descartes, to wit: there must be at least as much formal reality or formal perfection in the ultimate total efficient cause of an idea as there is objective reality in the idea itself.
(a)  The reason for the qualifier "ultimate" is that although one idea can be the effect of another idea (which has as much or more objective reality than the first idea), which can in turn be the effect of another idea (which has as much or more objective reality than the second idea), and so on, nevertheless one cannot go to infinity in a causal series of ideas wherein each idea is the effect of its predecessor.  That is to say, formal reality ultimately must stand causally behind objective reality.

5.  Descartes now concludes that if he has an idea whose objective reality is greater than his own formal reality, then its ultimate cause must lie outside him, and therefore he is not alone in the universe.  That is to say, solipsism will have been defeated.

6.  When he takes inventory of the ideas in his mind, Descartes finds the following:  ideas of himself, of God, of inanimate corporeal things, of other humans, of angels (purely immaterial substances), and of animals.  Descartes recognizes that his ideas of other humans, of angels, and of animals could all be fabricated out of his ideas of himself, of God, and of inanimate corporeal things, so it remains for him only to discover the causal source of his ideas of himself, of God, and of inanimate corporeal things.
(a)  Descartes could obviously be the causal source of his idea of himself; since he clearly has as much formal reality as the idea has objective reality.
(b)  Descartes notes that many of his ideas of body are so obscure and confused that it is unclear whether they represent anything positive, i.e., these ideas might have little or even no objective reality and so he could easily be their formal cause.  And with respect to his clear & distinct ideas of inanimate corporeal things, Descartes notes that he might be their source as well, because he can get the ideas of substance, number, and duration from himself and his own mental experience, and because all the other elements in his ideas of corporeal things -- extension, shape, position, movement -- are merely modes of substance, and so their formal reality or formal perfection might well be contained eminently in him, since he is a substance.
(c)  Only the idea of God remains as possibly outstripping his own causal powers.

7.  The fact that Descartes is a substance (a thing that thinks) does not give him enough formal reality to be the cause of the idea of infinite substance -- unless the idea of an infinite substance is a negative idea like the idea of darkness (the absence or negation of light).  But the idea of an infinite substance is not a negative idea, because Descartes sees clearly that infinite substance has more formal reality or formal perfection than finite substance has.  Also, because the idea of perfection is prior to that of imperfection, Descartes could not recognize his own imperfections (e.g., doubting) unless he had the idea of a perfect being.

8.  Nor could the idea of God be materially false (like the idea of cold or hot) and so come from nothing, because it is the clearest and most distinct idea Descartes has, containing more objective reality than any of his other ideas.  Anything he knows to have formal reality or perfection, he knows to exist in God either formally or eminently.

9.  But perhaps Descartes has underestimated himself, perhaps he contains all the divine perfections potentially.  After all, his knowledge increases gradually, so perhaps someday his knowledge will have increased to infinity.  But he recognizes that there is no potency in God, so the fact that his perfections are not fully actual is enough to show that his formal reality is inferior to that of God.  Besides, he recognizes that no matter how long it increases, his knowledge will never become infinite.

10.  Descartes now asks a new question: Could he exist with his idea of God if God did not exist?  The possible causal sources of his being under the hypothesis that God does not exist are himself, his parents, or some being or beings inferior to God.
(a)  If he were the source of himself with his idea of God, Descartes would have ideas of all the attributes of God and so would have made himself perfect.  As he puts it, it would be far more difficult to bring himself into existence from nothingness than to increase his knowledge and power to infinity.  So, he isn't the source of himself with his idea of God.
(b)  Even if he always existed, there would have to be a total cause of his being at every moment of its existence, since creation and preservation in being differ only conceptually, and since he is aware of no power to preserve his own existence, he doesn't possess such power because he'd be aware of it if he had it.
(c)  Neither his parents nor any being(s) inferior to God could have made him with his idea of God because any such cause must be a thinking thing that also has the idea of God.  If this being derives its existence from no other cause, it is God.  If it derives its being from some cause, one can ask where that cause gets its existence.  But one cannot go to infinity in a causal series of beings whose existence is caused by their predecessors.
(d)  Nor can Descartes with his idea of God be ultimately the effect of several causes acting together, since the simplicity and unity of God is one of his chief attributes.

11.  Therefore, God exists because Descartes exists and has the idea of a perfect, infinite being.  (This idea is implanted in him by God, i.e., it is one of Descartes's innate ideas.)

Having established that his idea of God comes from God himself, Descartes turns to how God causes him to have this idea. How does God do this?

Descartes appeals to the light of nature (the natural light) to justify the inference from God's nature to God's not being a deceiver. How does this argument go?

Meditation Four: Concerning the true and the false.

Of what is Descartes certain at the beginning of this meditation? How, generally speaking, does he propose to become certain of other things? (Hint: His way involves appeal to God's veracity.)

The ability to deceive is surely a perfection, so why does Descartes think that it is impossible for God to deceive?

Could God have placed in me a power or faculty such that, even at times when I use it properly, I nevertheless err or make mistakes? Why not?

At this stage of the meditation it appears that I am infallible, that I cannot err or make a cognitive mistake. Formulate the argument that seems to lead to this conclusion. (Professor Massey calls it Descartes's first paradox of error.)

How satisfactory a response to the first paradox of error is the observation that I am a finite being somehow suspended between infinity and nothingness and that consequently many of my cognitive operations are defective? If error were merely a negation (the mere absence of something) rather than a privation (the absence of something that is due, i.e., the absence of something that ought to be present) would the response be satisfactory?

What Professor Massey calls Descartes's second paradox of error is his argument to the conclusion that it is better to err than not to err. The principal premiss of this argument is the proposition that God could have made me so that I never err. What are the other premisses? What is the precise conclusion? How does the argument go?

Why does Descartes think it both rash and useless to inquire into final causes (the reasons or ends or purposes of things) in the realm of nature? Does he himself ever engage in such inquiries?

Does it follow from the fact that something (e.g., my mind) is imperfect, that God's creation is imperfect? Why not?

Descartes thinks that error results from the joint action of intellect (the faculty of knowing) and will (the faculty of choosing) . Explain exactly how he thinks error arises.

Might my intellect have been greater than it is? How? Could my will have been greater than it is? Why not? Is my will equal to God's will? In what respects? In what respects is God's will greater than my will?

In what does freedom of the will consist when one is judging and choosing? Is freedom of the will the same thing as indifference? If my intellect were so penetrating and capacious that I always saw clearly and distinctly what was true, and if I similarly always recognized the good, I would never err and never sin. Would I then be free?

If I refrain from assenting to anything that I do not clearly and distinctly perceive, will I ever err? Can I so refrain? Is God responsible for the fact that I don't always refrain from rash judgment? Why not?

Could God, without compromising my freedom or my finitude, have fashioned me so that I never err? In what two ways could He have done this? Isn't He therefore culpable for not having done so? Can I myself bring it about that I never err? How?

Isn't God at fault for giving me a will that outstrips my intellect? Isn't He at fault for lending His creative concurrence to my will when it affirms something which is not clearly and distinctly perceived by my intellect?

At the end of the fourth meditation Descartes appeals to veracity to ground the infallibility of the clear-and-distinct-ideas criterion. How does his argument go? Was it God's veracity, then, that made Descartes certain of his own existence when he clearly and distinctly perceived that he existed way back in the 2d meditation? If not, why is this appeal to veracity needed? Is it circular?

Fifth Meditation: Concerning the essence of material things and again concerning God and that He exists.

[Caution to Students: In some ways the 5th meditation is the most difficult of all the meditations to understand. First, it is not about physical bodies, as its title might lead you to expect. Rather, it is about extension in general and in abstraction from whether extended things exist in an external world. (Remember that Descartes identifies body or corporeal nature with extension.) Descartes is inquiring into the essence of mathematical objects, i.e. figures and numbers, and not into the essence of physical bodies existing in an external world . Second, the fifth meditation is concerned to eliminate the hyperbolical or metaphysical doubt which Descartes raised about mathematical knowledge in the first meditation; he is not here concerned to remove his doubts about an external world which remain very much in force. Third, Descartes seems to appeal to the veracity of God to ground the clear-and-distinct-ideas principle, and yet he seems to need this very principle to arrive at the existence and attributes of God. That is, it begins to appear as if Descartes's grand undertaking is viciously circular. In fact, Descartes appeals to divine veracity in this meditation, not to underwrite the clear-and-distinct-ideas principle itself, but to underwrite what might be called a memory-of-clear-and-distinct-ideas principle. This latter is used to make knowledge habitual (perfect) rather than ephemeral (imperfect or variable).]

What questions does Descartes temporarily set aside in order to deal with the urgent question of whether he is certain of anything about extension (body or corporeal nature)?

Rather than inquire whether corporeal things exist, Descartes begins by asking whether our ideas of them have certain properties. Which properties? Why does he start here?

Why does Descartes think that mathematical objects (corporeal nature), viz., figures and numbers, have their own true and immutable natures? Might they not be figments or constructions of his own mind? Even if they were figments of his own mind, couldn't he still demonstrate or prove things about them? Could we get our mathematical ideas, e.g., our ideas of figures, from our senses?

Why is it important to Descartes to show that mathematical objects have true and immutable natures? What are the consequences of their having such natures for proof or demonstration of their attributes or properties?

Does Descartes doubt a mathematical truth, e.g., the Pythagorean theorem, while he is attending to its demonstration? Why not? Does he then, i.e., while attending to the proof, clearly and distinctly perceive that the square on the hypotenuse equals the square on the other two sides of a right triangle?

Geometrical demonstration in which the properties of a thing are deduced from the idea or concept of it suggests to Descartes that one might similarly deduce God's existence from the idea or concept of God. (Such an argument for the existence of God is known as an ontological argument. Such arguments were first advanced by Saint Anselm of Canterbury in the 11th century.) Set out Descartes's version of the ontological argument. How cogent does Descartes think it is? As cogent as mathematical demonstrations? As cogent as the Cogito?

Descartes responds to three objections one might level against his ontological argument. These objections are, first, that because one can always distinguish essence (what a thing is) from existence, one can without contradiction deny that God exists, something that wouldn't be possible if the idea of God entails existence. Second, the argument proves only that I cannot think of God as non-existent, something quite compatible with God's not existing. Third, the argument is a petitio principii, i.e., it begs the question by building existence into the concept of God and then deriving from that concept what had expressly been put into it. How does Descartes answer these objections?

Why does Descartes think that our idea of God represents a true and immutable nature? Why does he care? Would his ontological argument work if the idea of God were a construction of his own mind?

Explain how Descartes uses divine veracity to eliminate doubt about propositions that he once clearly and distinctly perceived to be true but now only remembers having once clearly and distinctly perceived them. Why is he concerned to validate this rnemory-of-clear-and-distinct-ideas principle? What can this new principle do that the old clear-and-distinct-ideas principle can't do? How does it eliminate the hyperbolical doubt about mathematical truths?

Sixth Meditation: Concerning the existence of material things and the real distinction of the mind from the body.

How does Descartes use the principle that God can bring about, exactly as he Descartes conceives it, anything that he Descartes can clearly and distinctly perceive in order to prove that material things can exist, at least as objects of pure mathematics? Can God bring about something that is incompatible with our clear and distinct ideas?

What is the faculty of imagination? How does it differ from the intellect? Is it part of my nature, of what I am essentially? Is it needed to do mathematics?

Descartes argues that his possession of the faculty of imagination makes it probable that there is an external world, i.e., that material things such as his body exist. How does his argument go?

Descartes rehashes at length the arguments of the first meditation that show that all of our sense-based knowledge is doubtful? Is anything new added here? Anything subtracted?

Having banished hyperbolical doubt by his appeal to divine veracity, Descartes now sees himself in a better position to find some sense-based knowledge which is indubitable. The first thing he does is show that the mind and the body are really distinct by invoking the principle that God can bring about, exactly as he Descartes conceives it, anything that he Descartes can clearly and distinctly perceive. What is meant by the real distinction of mind and body? How does Descartes's argument for the real distinction go?

Descartes proves that there is an external world by showing that God would be a deceiver unless our adventitious sense ideas were not caused by bodies existing apart from us. How does his reasoning run?

What is the chief lesson that nature teaches the composite mind and body? In what way are the mind and body united or joined?

Does my desire to ingest a pleasant-tasting poison show that my composite nature, and hence God who is its author, has deceived me? Why not? Does the desire for water of someone suffering from edema (dropsy) show that his or her composite nature has deceived him or her? Why does it seem to be deception in this second case but not in the first one? How does Descartes show that God is not culpable for this apparent deception? In what way is Descartes's solution probabilistic? How good is his case?

For Descartes, what determines which ideas in the mind will arise from movements or disturbances in the brain? What purpose or function does this arrangement serve? How do we come to know it: by pure thought or by experience?

Considerations of divisibility lead Descartes to a second and independent argument for the real distinction of mind and body Formulate the argument.

Why does Descartes reject the answer based on the corruption of the body to his dropsy predicament that seems to convict God of deception? What is the analogy with the broken clock supposed to show?

Having disposed of dropsy-like cases, Descartes thinks that he has finally overcome hyperbolical doubt about sense-based knowledge? How does the divine veracity enter into this solution? How in particular does Descartes put to rest the worry raised in the first meditation that he might after all just be dreaming that there is an external world?


            SIXTH MEDITATION {Short Essay Topic}

A. Descartes's First Argument for the Real Distinction of Mind and Body

1. What does Descartes mean when he says that x is really distinct from y?

a. That God can bring it about that x exists separately from y.

b. That x can exist apart and independently from y.

2. What causal principle does Descartes employ to establish the real distinction of mind and body?

Causal Principle: God can bring about whatever Descartes can clearly and distinctly conceive in such a way that what is
brought about conforms exactly to his conception of it.

Example: Body (bodies or material things) can exist because Descartes has a clear and distinct idea of body (extension) in pure

3. What conceptual premiss does Descartes argue from?

Conceptual Premiss: That he has a clear and distinct conception of himself as a mind (thinking substance) without a body, and
of his body apart from himself as mind. That is, he can clearly and distinctly conceive of himself as a mind existing without a
body, and of his body existing apart from himself as mind. (Descartes purports to have established these claims in the Second

4. How does the argument go?

Conceptual Premiss: Descartes has a clear and distinct conception of himself as a mind (thinking substance) without a body,
and of his body apart from himself as mind. That is, he can clearly and distinctly conceive of himself as a mind existing without a
body, and of his body existing apart from himself as mind.

Causal Premiss: God can bring about whatever Descartes can clearly and distinctly conceive in such a way that what is brought
about conforms exactly to his conception of it.

First Conclusion: God can bring it about that Descartes is himself a mind without a body, and also bring it about that his body
exists apart from him as a mind.

Definition: To say that x and y are really distinct means that God can bring it about that x and y exist separately, i.e., God can
bring it about that x and y exist apart and independently.

Final Conclusion: Descartes's mind and body are really distinct.

B. Descartes's Second Argument for the Real Distinction of Mind and Body

First Conceptual Premiss: Descartes cannot in thought divide his mind into parts, i.e., he cannot conceive of his mind as

Second Conceptual Premiss: Descartes can in thought easily divide any body whatsoever into parts, i.e., he can clearly and
distinctly conceive of any body as divisible.

Causal Premiss: What is divisible is really distinct from what is indivisible.

Conclusion: Descartes's mind is really distinct from his body.


             EXTERNAL WORLD {Long Essay Topic}

1. By invoking the causal principle that God can bring about whatever Descartes can clearly and distinctly conceive in such a
way that what is brought about conforms exactly to his conception of it, Descartes is able to conclude that the clarity and
distinctness of his geometrical ideas shows that material bodies (real extension) can exist. It remains, however, an open question

whether they do exist.

2. Imagination and understanding are different activities. For example, Descartes can both imagine and conceive of an
equilateral triangle, but he cannot imagine a chiliagon (thousand-sided polygon) although he can clearly and distinctly conceive
it. Because Descartes can clearly and distinctly conceive of himself existing as a mind without the faculty of imagination,
nlyunderstanding belongs to him essentially.

3. Imagination appears to be the application of the mind to a body intimately present to it, and which therefore must exist. From
the fact that there is no other account of imagination as good as the one just given, Descartes concludes that it's probable that,
when he imagines something, his mind is intimately present to an actually existing body. Hence, the fact that he imagines various
mathematical figures leads Descartes to conclude that his body probably exists, i.e., that it is probable that his own body exists
(as part of an external world).

4. Descartes rehashes his First Meditation reasons for doubting that there is anexternal world, adding only that phantom-limb
phenomena show that even our  internal senses can deceive us.

5. Because he is nothing but a mind (a thinking thing really distinct from his body), Descartes takes it for granted that he cannot
himself be the source of his adventitious sense ideas (e.g., his sense perceptions) because he would then be aware of his willing

6. Invoking the causal principle that there must be at least as much formal reality in the cause of an idea as there is objective
reality in the idea itself, Descartes concludes that his sense ideas (sense perceptions and sensations) must come from bodies,
from God, or from some being intermediate in perfection between bodies and God.

7. Invoking our strong inclination to attribute many of our sensations and sense perceptions to the material bodies from which
they appear to come, Descartes concludes that God would be a malicious deceiver if the source of these sensations and ideas
were either God Himself or some intermediate creature more perfect than bodies, because we would then have no way to
correct our strong propensity to attribute these sensations and perceptions to material bodies existing in an external world.

8. Since God is not a deceiver, Descartes concludes that he really does have a body and that material bodies are the actual
sources of our sensations and sense perceptions, i.e., that his body exists (as part of an external world).


SIXTH MEDITATION  {Short Essay Topic}

1.  What does Descartes say that his nature, in the sense of the totality of things conferred on him by God, teaches him?  What
does it appear to teach him that it really does not teach him?

     Descartes says that his nature in the aforesaid sense teaches him that he has a body; that when he feels pain there is
something wrong with his body; that when he is thirsty, his body needs a drink; that his mind is not present to his body as a
sailor in his ship but rather that his mind is so intimately joined or fused with his body that they form a composite unit; that other
bodies exist in the vicinity of his body; and that some of these other bodies should be sought out or pursued, whereas others of
them should be avoided.   Descartes thinks that his nature in the aforesaid sense also appears to teach him such things as that
there is absolutely nothing in a empty space (in a vacuum); that the heat or color in a body exactly resembles his ideas of the
heat and color; and that physical objects have the size and shape which they present to his senses.  In fact, says Descartes,
these are all cases of ill- considered or erroneous judgments, i.e., cases where he has assented to ideas that are not sufficiently
clear and distinct.

2.  What does Descartes think that his nature, in the sense of the composite of his mind and body, teaches him?  What does it
appear to teach him that it really does not teach him?

     Descartes thinks that his nature, considered as the composite of his mind and body, teaches him to avoid things that induce
pain and to pursue things that induce pleasure.  That is to say, the natural purpose or function of his sensations and sense
erceptions is to inform him about what is beneficial and what is injurious to the composite of mind and body.  For example, his
nature (as the composite of mind and body) teaches him that he should drink when he is thirsty (because his body then needs
liquid), should eat when he is hungry (because his body then needs food), and should pull back his hand when it touches
something that makes him feel pain (because the thing touched is harming his hand).      What nature as the composite of mind
and body does not teach him, saysDescartes, is anything about the properties of objects external to him.  Truth about external
objects is determined by the mind alone, not by the composite of mind and body.

3.  When someone desires to eat a sweet-smelling and sweet-tasting poison, doesn't his nature (as the composite of mind and
body) make a grave error about what is beneficial to the composite?  If so, doesn't this convict the Creator of malicious

     The person's nature (as the composite of mind and body) teaches him to pursue the good taste, not the poison.  The
fortunate fact that what tastes good is in this case also poisonous shows only that the person's nature is not omniscient; it does
not show that his nature misled him, but only that it has made an accidental mistake.      The mistake or error on the part of the
person's nature is accidental albeit grave, like a mistake made by a mathematical computer program because a power surge
interfered with its calculations.  The mistake or error is not systematic or intrinsic, like the mistakes made by a mathematical
program that has some bugs in it.  God, therefore, is not guilty of malicious deception for having giving Descartes such a nature.

4.  If God had given Descartes a nature (as a composite of mind and body) that makes systematic or intrinsic mistakes, God
would be guilty of malicious deception.  But when Descartes experiences thirst when suffering from dropsy, his nature (the
composite of his mind and body) is instructing him to drink because his body needs more liquid, which is simply false.  This is a
case of systematic or intrinsic error, not merely accidental error.  God, therefore, is a malicious deceiver.

     Descartes concedes that if God had given him a nature that makes systematic or intrinsic mistakes, God would indeed be a
malicious deceiver -- but only if God could have done better.  It's true that from time to time his nature (as the composite of
mind and body) does mislead him systematically or intrinsically, e.g., when thirst prompts him to drink when he is suffering
from dropsy, because what his nature then impels him to do is to consume liquid, which is in fact bad for his body in the
circumstances.  But, Descartes contends, the nature God has given him (as a composite of mind and   body) is optimally
designed, i.e., it is the best design possible for a creature composed of mind and body.  But no one should be blamed for doing

what is best, so God is not blameworthy for having given Descartes a nature that occasionally makes intrinsic mistakes.  God,
therefore, is not a malicious deceiver.

5.  What is Descartes's argument for his claim that his nature (as a composite of mind and body) is optimally designed?

     The argument runs thus:  The mind is immediately affected by only one part of the body, namely, the brain (or perhaps one
particular part of the brain, viz., the pineal gland).  A state [of motion] of the brain (or of the pineal gland) sends exactly the
same signals to the mind, irrespective of the states of other organs or other parts of the body.  The body is a mechanical
system, so when a part A is moved by a part D by means of  intermediate parts C and B, part A would be moved exactly the
same way if part D didn't move at all while parts C and B moved as before.  For example, stubbing the big toe of your left foot
on a rock causes motions in the toe and foot that cause motions in the   nerves that ultimately cause a motion in the brain that
affects the mind in such a way that you experience pain in your left foot, so the same motions in the nerves near your brain
would cause the same brain state and thus occasion the same mental experience of pain in your left foot even if your left foot as
resting comfortably on a footstool or even if your left foot had been amputated.  Experience shows that the correlation of brain
states (pineal gland states) and mental states has the following property: Of all possible mental states, each brain state occasions
that particular mental state that would most benefit the mind-body composite in most of life's circumstances.  That is, for each
brain state, the correlation of any other mind state with it would result in an arrangement less beneficial overall to the mind-body
composite.  Thus, although the correlation of the feeling of thirst with the brain state caused by dryness of the mouth will
casionally result in a desire to drink in circumstances where drinking is harmful to the body, e.g., as in a person with dropsy, in
most cases where the brain is in the aforesaid state, drinking will be beneficial to the body.  Thus, the correlations of mind states
with brain states in our nature (as composites of mind and body) is the best possible arrangement so far as the well being of
the mind-body composite goes.  In other words, Descartes's nature is optimally designed.

6.  Can Descartes say anything else on behalf of God's veracity?

     Yes, he can and does.  Descartes points out we can correct the systematic or intrinsic errors made by our nature (as the
composite of mind and body) by employing several senses instead of just one, and by using our intellect and our memory.  For
example, if we suffer from dropsy, we can correct what our sensation of thirst tells us (that we need to drink) by recalling that
medical science has shown that drinking is harmful to someone suffering from dropsy. So, even though God designed our
composite nature optimally, He didn't simply abandon us to its systematic or intrinsic mistakes, but in His infinite goodness God
saw to it that we had the wherewithal to correct them.