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Descarte 2 Essay, Research Paper

Descartes

How does Descartes try to extricate himself from the sceptical

doubts that he has raised? Does he succeed?

by Tom Nuttall

[All page references and quotations from the Meditations are

taken from the 1995 Everyman edition]

In the Meditations, Descartes embarks upon what Bernard Williams

has called the project of ‘Pure Enquiry’ to discover certain,

indubitable foundations for knowledge. By subjecting everything

to doubt Descartes hoped to discover whatever was immune to it.

In order to best understand how and why Descartes builds his

epistemological system up from his foundations in the way that he

does, it is helpful to gain an understanding of the intellectual

background of the 17th century that provided the motivation for

his work.

We can discern three distinct influences on Descartes, three

conflicting world-views that fought for prominence in his day.

The first was what remained of the mediaeval scholastic

philosophy, largely based on Aristotelian science and Christian

theology. Descartes had been taught according to this outlook

during his time at the Jesuit college La Flech_ and it had an

important influence on his work, as we shall see later. The

second was the scepticism that had made a sudden impact on the

intellectual world, mainly as a reaction to the scholastic

outlook. This scepticism was strongly influenced by the work of

the Pyrrhonians as handed down from antiquity by Sextus

Empiricus, which claimed that, as there is never a reason to

believe p that is better than a reason not to believe p, we

should forget about trying to discover the nature of reality and

live by appearance alone. This attitude was best exemplified in

the work of Michel de Montaigne, who mockingly dismissed the

attempts of theologians and scientists to understand the nature

of God and the universe respectively. Descartes felt the force of

sceptical arguments and, while not being sceptically disposed

himself, came to believe that scepticism towards knowledge was

the best way to discover what is certain: by applying sceptical

doubt to all our beliefs, we can discover which of them are

indubitable, and thus form an adequate foundation for knowledge.

The third world-view resulted largely from the work of the new

scientists; Galileo, Copernicus, Bacon et al. Science had finally

begun to assert itself and shake off its dated Aristotelian

prejudices. Coherent theories about the world and its place in

the universe were being constructed and many of those who were

aware of this work became very optimistic about the influence it

could have. Descartes was a child of the scientific revolution,

but felt that until sceptical concerns were dealt with, science

would always have to contend with Montaigne and his cronies,

standing on the sidelines and laughing at science’s pretenses to

knowledge. Descartes’ project, then, was to use the tools of the

sceptic to disprove the sceptical thesis by discovering certain

knowledge that could subsequently be used as the foundation of a

new science, in which knowledge about the external world was as

certain as knowledge about mathematics. It was also to hammer the

last nail into the coffin of scholasticism, but also, arguably,

to show that God still had a vital r_le to play in the discovery

of knowledge.

Meditation One describes Descartes’ method of doubt. By its

conclusion, Descartes has seemingly subjected all of his beliefs

to the strongest and most hyberbolic of doubts. He invokes the

nightmarish notion of an all-powerful, malign demon who could be

deceiving him in the realm of sensory experience, in his very

understanding of matter and even in the simplest cases of

mathematical or logical truths. The doubts may be obscure, but

this is the strength of the method – the weakness of criteria for

what makes a doubt reasonable means that almost anything can

count as a doubt, and therefore whatever withstands doubt must be

something epistemologically formidable.

In Meditation Two, Descartes hits upon the indubitable principle

he has been seeking. He exists, at least when he thinks he

exists. The cogito (Descartes’ proof of his own existence) has

been the source of a great deal of discussion ever since

Descartes first formulated it in the 1637 Discourse on Method,

and, I believe, a great deal of misinterpretation (quite possibly

as a result of Descartes’ repeated contradictions of his own

position in subsequent writings). Many commentators have fallen

prey to the tempting interpretation of the cogito as either

syllogism or enthymeme. This view holds that Descartes asserts

that he is thinking, that he believes it axiomatic that ‘whatever

thinks must exist’ and therefore that he logically concludes that

he exists. This view, it seems to me, is wrong. It should be

stated on no occasion, in the Meditations, does Descartes write

‘I am thinking, therefore I am’, nor anything directly

equivalent. Rather, he says:

“Doubtless, then, that I exist and, let him deceive me as

he may, he can never bring it about that I am nothing, so long as

I shall be conscious that I am something. So that it must, in

fine, be maintained, all things being maturely and carefully

considered, that this proposition I am, I exist, is necessarily

true each time it is expressed by me or conceived in my mind.”

(p. 80).

The point here is that it is impossible to doubt the truth of the

proposition ‘I exist’ when one utters it. It is an indubitable

proposition, and one that will necessarily be presupposed in

every attack of the sceptic. Descartes is not yet entitled to use

syllogisms as the possibility of the malign demon is still very

much alive. As an aside, Descartes himself denies that the cogito

is a syllogism, although it should be mentioned that in some of

the Replies to Objections he seems to assert that it is in fact

a syllogism. Finally, in the Regulae ad directionem ingenii,

Descartes denies the usefulness of syllogisms as a means to

knowledge.

I believe that, given Descartes’ project, it is fair to grant him

that the cogito deserves the status he bestows upon it. For can

there be anything more certain than something that is so forceful

and so powerful that every time it is presented to our mind we

are forced to assent to it?

What Descartes did here was to jiggle about the way philosophy

normally approaches the construction of knowledge structures. By

starting with self-knowledge, he elevates the subjective above

the objective and forces his epistemology to rest upon the

knowledge he has of his own self (and inadvertently sets the tone

for the next 300 years of philosophy). This leaves him with a

problem. He can know his own existence, that he is a thinking

thing and the contents of his consciousness, but how can any of

this ever lead to any knowledge of anything outside of himself?

The answer is that, by itself, it can’t. Descartes, in the third

Meditation, attempts to prove the existence of God, defined as a

being with all perfections. This proof is to be derived from his

idea of a God, defined as a being with all perfections. So far,

so good – Descartes examines the contents of his consciousness

and discovers within it this idea, and we can allow him this. At

this point, however, he introduces a whole series of scholastic

principles concerning different modes of causation and reality

without proper justification:

“For, without doubt, those [ideas considered as images, as

opposed to modes of consciousness] that represent substances are

something more, and contain in themselves, so to speak, more

objective reality, that is, participate by representation in

higher degrees of being or perfection than those that represent

only modes or accidents; and again the idea by which I conceive a

God has certainly in it more objective reality than those ideas

by which finite substances are represented.

Now it is manifest by the natural light that there must be

at least as much reality in the efficient and total cause as in

its effect; for whence can the effect draw its reality if not

from its cause? And how could the cause communicate to it this

reality unless it possessed it in itself?”

Whence do these principles draw their indubitability? Even if we

grant that it is contrary to natural reason that an effect can

have greater ‘reality’ than its cause, that the concepts of modes

and substances are coherent with Descartes’ method, let alone

possess the properties that he ascribes to them, then surely we

can still bring the malign demon into play? Is it not possible

that this all- powerful demon could bring it about that Descartes

has a notion of a being with all possible perfections that he

calls God? No, says Descartes, because the notion (representing

something perfect) would then have more objective reality than

the demon (as something evil and thus imperfect) has formal

reality, and ‘it is manifest by the natural light’ that this is

not possible. But why not? Maybe the demon has just made it seem

impossible, and it seems that Descartes has no answer to this.

Further problems remain. Cosmological arguments for God invoking

the notion of causation have always had to contend with the

problem of the cause of God. For if all events (or ideas) are

caused ultimately by God, then what about God Himself? Why should

He be exempt from this rule? The standard response to this is to

claim that God, being omnipotent, causes Himself. One of the

chief perfections that Descartes attributes to God is that of

’self-existence’, that is, that His existence depends on nothing

else but itself. But if we examine this idea, it seems a little

confused. If God is the efficient cause of God then we are forced

to ask how something that does not yet exist can cause anything.

If God is the formal cause of God, i.e. it is part of the

intrinsic nature of God that he exists – which seems more likely

- then it seems that we have merely a reformulation of the

ontological argument for God’s existence from Meditation 5.

It seems that Descartes may have anticipated the wealth of

criticism that the causal proof of God would inspire, and so,

after explaining how human error and a benevolent, non-deceiving

God are compatible in Meditation Four, he produced in Meditation

Five a version of the mediaeval ontological argument for God’s

existence. Unlike the causal argument, the ontological argument

doesn’t involve the covert import of any new principles. It

simply purports to show that, from an analysis of his own idea of

God, Descartes can show that He necessarily exists. The reasoning

goes like this:

I have ideas of things which have true and immutable natures. If

I perceive clearly and distinctly that a property belongs to an

idea’s true and immutable nature, then it does actually belong to

that nature. I perceive clearly and distinctly that God’s true

and mmutable nature is that of a being with all perfections.

Further, I perceive clearly and distinctly that existence is a

perfection and non-existence a non- perfection. Thus existence

belongs to God’s true and immutable nature. God exists.

One of the interesting things about this argument is that, at

first sight, it does not seem to depend in any way upon anything

that has been proved hitherto. It is an application of pure

logic, an analysis of what we mean when we say ‘God’ and a

inference from that analysis. Descartes explicitly says that an

idea’s true and immutable nature does not in any way depend upon

his thinking it, and thus upon his existence. Once he has

perceived clearly and distinctly that an idea’s true and

immutable nature consists in such-and-such, that is the case

whether or not he thinks it is, or even if he exists or not.

Descartes in fact recognises the primacy of the ontological

argument: “although all the conclusions of the preceding

Meditations were false, the existence of God would pass

with me for a truth at least as certain as I ever judged any

truth of mathematics to be.” If this is true, which it seems to

be, then this argument is only as trustworthy as the faculties

which enabled us to construct it, which are the same faculties

that enable us to know mathematical truths, and so it seems

worthwhile to ask how, under Descartes’ theory, we come to know

mathematical truths. Descartes claims we perceive them clearly

and distinctly. How do we know that what we perceive clearly and

distinctly is true? Because God, being perfect, is no deceiver,

and would not let it be the case that we could ever perceive

something clearly and distinctly without it being the case. It

seems then, that this proof of God, relying on the veracity of

clear and distinct ideas, relies on the certain knowledge that a

non-deceiving God exists. We have another proof of God, the

causal proof as described in Meditation three. But apart from the

patent futility of using one proof of p to construct another

proof of p, on examining the causal proof of God further, we find

that it, too, relies upon a methodology that can only be relied

upon if the divine guarantee is present, for if this guarantee is

not present, then, as I mentioned above, how can we be sure that

the all-powerful demon is not exercising his malignant influence?

This, of course, is the infamous Cartesian circle, first

identified by Arnauld in the Fourth Objections and discussed ever

since. Many philosophers have tried to get Descartes off the hook

in various ways, some by denying that there is a circle and some

by admitting the circularity but denying its significance. I will

here briefly evaluate a few of their arguments.

Some commentators have taken a passage from Descartes’ reply to

the Second set of Objections (Mersenne’s) to indicate that

Descartes is only actually interested in the psychological

significance of fundamental truths. The passage is as follows:

“If a conviction is so firm that that it is impossible for us

ever to have any reason for doubting what we are convinced of,

then there are no further questions for us to ask; we have

everything we could reasonably want.”

Under my interpretation, this is what it is about the cogito

that makes it so important for Descartes, so we cannot have any

argument with the principle expressed by him in the above

passage. But can it help break the circle? When we clearly and

distinctly perceive something, Descartes says, fairly I think,

that this perception compels our assent, that we cannot but

believe it. God’s r_le in the system, to these commentators, is

as a guarantor of our memory regarding clarity and distinctness.

In other words, once we have proved God’s existence, we can

happily know that any memory we have of a clear and distinct idea

regarding x is true i.e. that we really did have a clear and

distinct idea of x. But this does not seem satisfactory, as we

still do not have a divine guarantee for the reasoning that leads

us from the clear and distinct notions we originally have about

God to the proof of His existence. We can give assent to the

clear and distinct notions we have originally; in fact, we are

compelled to give this assent when the notions are presented to

our mind, but the logical steps we take from these ideas to the

final proof is still subject to the evil demon because God is not

yet proven. Furthermore, because these steps are needed, the

memory of the original clear and distinct ideas are themselves

subject to doubt because God is not yet proven. It seems that the

only way either of the proofs of God could be accepted would be

if we had an original clear and distinct perception of God

directly presented to our mind (qualitatively similar to the

cogito). But this in itself would make any future proofs

redundant. Interestingly, this sounds quite similar to a divine

revelation.

Harry Frankfurt, in his book ‘Demons, Dreamers and Madmen’, has

argued that what Descartes is actually looking for is a coherent,

indubitable set of beliefs about the universe. Whether they are

‘true’ or not is irrelevant. Perfect certainty is totally

compatible with absolute falsity. Our certainty may not coincide