conclusion.
Regarding the nature of corporeal bodies and our knowledge of
them, it seems to me that, given his premises, the conclusions
Descartes draws in Meditation Six are generally the correct ones.
He again invokes the causal to argue that the ideas of bodies we
have within our minds must be caused by something with at least
as much formal reality as the ideas have objective reality. We
could theoretically be producing these ideas, but Descartes
dismisses this possibility for two reasons – firstly, that the
idea of corporeality does not presuppose thought and secondly
that our will seems to have no effect on what we perceive or
don’t perceive. (This second argument seems to me to ignore
dreaming, in which what we perceive derives from us but is
independent of our will). The ideas, then, could come from God,
or from another being superior to us but inferior to God. But
this, too, is impossible, argues Descartes, as if it were the
case that God produces the ideas of bodies in us, then the very
strong inclination we have towards believing that the idea-
producing bodies resemble the ideas we have would be false and
thus God would be allowing us to be deceived which is not
permissible. The same would apply if any other being were
producing these ideas. Thus, concludes Descartes, it is most
likely that our ideas of corporeal bodies are actually caused by
bodies resembling those ideas. We cannot be certain, however, as
we cannot claim to have clear and distinct notions of everything
we perceive. We can, however, claim certainty with regard to
those properties of bodies which we do know with clarity and
distinction; namely, size, figure (shape), position, motion,
substance, duration and number (not all of these assertions are
justified). Obviously we cannot claim that we know these
properties for specific bodies with clarity and distinction, for
to do so would leave open the uestion of why it is that
astronomy and the senses attribute different sizes to stars. What
Descartes means is that we can be sure that these primary
qualities exist in bodies in the same way that they do in our
ideas of bodies. This cannot be claimed for qualities such as
heat, colour, taste and smell, of which our ideas are so confused
and vague that we must always reserve judgement. (This conclusion
is actually quite similar to the one John Locke drew fifty years
later in his Essay Concerning Human Understanding.)
I think we can grant this reasoning, with the caveat regarding
dreaming that I noted above, and of course the other unproved
reasonings that Descartes exhumes here, such as the causal
principle. Furthermore, it seems to be further proof that
Descartes does believe we can get to know objects in themselves
to a certain extent.
Finally, I turn to Descartes’ argument for the distinction of
mind and body. Descartes believes he has shown the mind to be
better known than the body in Meditation Two. In Meditation Six
he goes on to claim that, as he knows his mind and knows clearly
and distinctly that its essence consists purely of thought, and
that bodies’ essences consist purely of extension, that he can
conceive of his mind and body as existing separately. By the
power of God, anything that can be clearly and distinctly
conceived of as existing separately from something else can be
created as existing separately. At this point, Descartes makes
the apparent logical leap to claiming that the mind and body have
been created separately, without justification. Most commentators
agree that this is not justified, and further, that just because
I can conceive of my mind existing independently of my body it
does not necessarily follow that it does so. In defence of
Descartes, Saul Kripke has suggested that Descartes may have
anticipated a modern strand of modal logic that holds that if
x=y, then L (x=y). In other words, if x is identical to y then it
is necessarily identical to it. From this it follows that if it
is logically possible that x and y have different properties then
they are distinct. In this instance, that means that because I
can clearly and distinctly conceive of my mind and body as
existing separately, then they are distinct. The argument, like
much modern work on identity, is too technical and involved to
explore here in much depth. But suffice to say that we can
clearly and distinctly conceive of Dr Jekyll and Mr. Hyde as
being distinct and yet they are identical, necessarily so under
Kripke’s theory. It is doubtful that Kripke can come to
Descartes’ aid here and Descartes needs further argument to prove
that the mind and the body are distinct.
And so we finish our discussion of Descartes’ attempts to
extricate himself from the sceptical doubts he has set up for
himself. As mentioned previously, the ultimate conclusion to draw
regarding the success of the enterprise that Descartes set for
himself must be that he failed. When the whole epistemological
structure is so heavily dependent on one piece of knowledge – in
this case the knowledge that God exists – then a denial of that
knowledge destroys the whole structure. All that we can really
grant Descartes – and this is certainly contentious – is that he
can rightly claim that when a clear and distinct idea presents
itself to his mind, he cannot but give his assent to this idea,
and furthermore, that while this assent is being granted, the
clear and distinct idea can be justly used as a foundation for
knowledge. The most this gets us – and this is not a little – is
the knowledge of our own existence each time we assert it. But
Descartes’ project should not be judged by us as a failure – the
fact that he addressed topics of great and lasting interest, and
provided us with a method we can both understand and utilise
fruitfully, speaks for itself.
Bibliography
1. Descartes, Ren_ A Discourse on Method, Meditations and
Principles of Philosophy trans. John Veitch. The Everyman’s
Library, 1995.
Descartes, Ren_ The Philosophical Writings of Descartes volume I
and II ed. and trans. John Cottingham, R. Stoothoff and D.
Murdoch. Cambridge, 1985.
Frankfurt, Harry Demons, Dreamers and Madmen. Bobbs-Merrill,
1970.
Curley, Edwin Descartes Against the Skeptics. Oxford, 1978.
Vesey, Godfrey Descartes: Father of Modern Philosophy. Open
University Press, 1971.
Sorrell, Tom Descartes: Reason and Experience. Open University
Press, 1982.
The Oxford Companion to Philosophy ed. Ted Honderich. Oxford
University Press, 1985.
Cottingham, John Descartes. Oxford, 1986. Williams, Bernard
Descartes: The Project of Pure Enquiry. Harmondsworth, 1978.
Russell, Bertrand The History of Western Philosophy. George Allen
and Unwin, 1961. 11. Kripke, Saul Naming and Necessity. Oxford
1980.>
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 rea