13 Descartes, Meditations V (cf., Discourse IV, AT VI 36-39) when
I first discover them, it seems I am not so much learning something new as
discovering something I knew beforehand. –
Descartes, Meditations V Having eliminated the demon deceiver argument
and his doubts about demonstrative sciences that just examine ideas and make
no existence claims, Descartes’s next job was to reassess the dreaming
argument and his doubts about the existence of other things outside of
himself, particularly including the bodies revealed by his senses. But before addressing this question, Descartes
declared that it might be wise to first consider his ideas of sensible
bodies, and identify what is clearly and distinctly perceived in those ideas. Descartes proceeded to focus on the positive
rather than the negative: on what is clearly and distinctly perceived in
these ideas rather than on what is not.
But all the same it is worth recalling something that was already
established in Meditations
III. We should not expect that
Descartes would include sensible qualities like color or heat among those
things that are clearly and distinctly perceived in our ideas of bodies. The sensible qualities are so far from
being clear and distinct that they
are not even clear. They are so
obscurely perceived that we can’t even tell them apart from what they are
not. This is because we can’t tell whether
they are ideas of real, positive things, or instead “materially false” ideas
of the absence of what is real and positive.
They do not figure on Descartes’s list of what is clearly and
distinctly perceived in our ideas of bodies. In contrast, extension and its “modes” or
modifications (shape, size, orientation, motion, number) are not only clearly
but also distinctly perceived. In
addition to having an idea of extension, we have ideas of its “parts,” that
is, of all the different ways in which it can be cut into shapes of various
sizes, and of the way these bits can be turned and moved and arranged. Moreover, even though we may doubt the
existence of an external world, containing anything that is extended, and
consider all our ideas of shapes to be nothing more than images in our minds,
these images have their own natures over which we have no control. For example, try as we might, we cannot
form an idea of more than four equidistant points. There is something about the nature of
extension itself that independently forbids us from doing this. Similarly, we cannot form ideas of cubes
with more or less than six faces, or of triangles with internal angles that
are not equal to two right angles or largest angles that are not opposite
their longest sides. Again there is
something about the nature of extension that, independently of us, forces our
thoughts about shapes to conform to particular laws, which we call the laws
of geometry. This compels us to
recognize extension as something that has a “reality” of its own and that
certainly is not materially false (nothing could not constrain our thoughts
to take on a certain form), even if extended objects may not exist outside of
us. It turns out, therefore, that what we really
know about sensible things is not what we originally thought. What we really know is just that they are
extended, and that their extension is susceptible of being modified in accord
with the laws of geometry and mathematics.
We do not know that they are coloured or hot, or even that they are
solid or heavy. That having been said,
it still remains a question of whether anything exists outside of us that
corresponds to these ideas. In addition to rehabilitating some of what we
thought we knew about sensible bodies, Meditations
V presents a further proof for the existence of God. Unlike the a posteriori and demonstrative proof of Meditations III, which starts from the fact that an idea of God
exists in me and asks what might cause this idea, this proof is an a priori proof, like the proofs
given in mathematics, which rests on an analysis of what is contained in the
idea of God. Descartes seems to have
wanted to make the point that the existence of God can be demonstrated in the
same way, and with the same degree of evidence, as any proposition of
mathematics. This would answer those
atheists who doubted the existence of God but still considered mathematical
propositions to be beyond doubt. But
he also went on to claim that knowledge of the existence of God is more fundamental
than any truth of mathematics. This is
because a prior proof of the existence of God is what eliminates the demon
deceiver objection, enabling us to be certain of what we clearly and
distinctly perceive not only at the time when we clearly and distinctly
perceive it, but also later, when we only remember having clearly and
distinctly perceived it. Not only
would an all-perfect God not want to deceive me, he would not allow any other
very powerful being to do so, and he would ensure that in any cases where I
am deceived I am supplied with some way of discovering my error. Were my memory so unreliable that even
frequent review of the same demonstration could leave me systematically
deceived, there would be no hope of discovering errors. We would have to go back to clearly and
distinctly perceive the matter all over again, and then we would be able to
make no progress beyond that point, to think about anything else. Memory must therefore not be so unreliable that, even in those
cases where we remember having repeatedly attended to the matter and clearly
and distinctly perceived the same result, we are misremembering. It is assurance of the existence of God
that establishes this, and so makes demonstration in the mathematical
sciences possible. QUESTIONS
ON THE
1. Which ideas of things
are distinct?
2. How is it that
Descartes could say that my ideas of geometrical shapes are not made by me,
even though I can imagine them on my own, and call them up or make them go
away at will?
1. How did Descartes
respond to the objection that I may have learned of geometrical shapes from
sensory experience of similarly shaped objects, and that the reason why I
seem to “remember” these shapes rather than to have produced them myself in
my own imagination is that I am really just remembering something I have seen
before?
2. Why, according to
Descartes, can existence not be separated from the “essence” (i.e., the
definition) of God?
3. How did Descartes
respond to the objection that I might arbitrarily attach the idea of existence
to the idea of God in my imagination, so that from the fact that I choose to
make this connection, it in no way follows that the connection must be true
and that God must exist?
4. How did Descartes
respond to the objection that just because I cannot imagine God without
attributing existence to him, it does not follow that God must exist because
my thought imposes no necessity on things?
5. Supposing that the
existence of God is not yet certain, under what circumstances would it be
possible to doubt what one has clearly and distinctly perceived?
6. How is it that all
demonstrations in mathematics might be said to rest on a prior demonstration
of the existence of God? NOTES
ON THE a. The reality of our ideas of extension and
its modes. Descartes opened Meditations V by turning to the
internal world of his ideas and asking which of them could be considered to
be ideas of things that are “real” or positive. In asking this question he was not asking
which of our ideas are of things that actually exist. For Descartes, the concepts of reality and
actual existence are importantly distinct.
Reality has to do with how things are described, that is, with the
sorts of characteristics or qualities that are ascribed to things. Actuality has to do with whether things
exist. Descartes shared the
traditional notion that the qualities that are ascribed to things come in
opposed pairs (e.g., bright and dark, hot and cold, light and heavy, moist
and dry). One member of each pair is
positive or real and the other is privative.
Positive qualities are something whereas privative qualities are
actually nothing — they arise from the absence of their positive
counterparts. Consequently, things can
be more or less “real” depending on how many positive qualities they have. Reality, in this sense, has nothing to do
with existence. Things that do not
exist, like dragons or unicorns, can nonetheless have positive qualities
(e.g., extension and motion). Things
that do exist, like ice or earth, have privative qualities (e.g., coldness
and darkness). There can be less
“reality” (fewer positive qualities) possessed by some things that do exist
than by other things that do not exist. Note that as far as our ideas are concerned,
existence is not in question. Just as
I cannot doubt that I exist, so I cannot doubt that my ideas exist. Indeed, the two are one and the same, since
for me to be aware of my existence just is for me to be aware of the thoughts
or ideas that are within me. However, we have already seen in Meditations III that the reality of
our ideas is in question. Our ideas of
sensible qualities are so obscure that we cannot tell for sure whether they
are materially false ideas of privations or real ideas of positive qualities. Descartes’s first job in Meditations V was to prove that at least some of our ideas are
unquestionably of real or positive things.
These are our ideas of the extension of things and of the ways this
extension can be modified. The idea of
extension is the idea of a quantity rather than a quality of things. Specifically, it is the idea of being
continuously spread out over three dimensions and being divisible into
differently located parts with different sizes and shapes and states of
motion or rest. (Number, location,
size, shape, and motion are ways in which parts of extension are modified, or
“modes” of extension.) Moreover, the
shapes are clearly and distinctly perceived to have certain natures. Triangular shapes, for instance, must have
internal angles equal to two right angles.
Right angle triangles must have their hypotenuse equal in length to
the square root of the sum of the squares of their sides. There are many propositions like this — all
the propositions of geometry. These
propositions are known simply by perceiving what is contained in our ideas of
different shapes. Descartes made an odd remark concerning these
judgments. He said that when I first
discover them it seems I am not so much learning something new as recalling
something I knew beforehand. The claim
is reminiscent of Plato’s assertion (e.g. in the Meno) that mathematical truths are recollected from an experience
had before birth when the soul, freed from the body, was able to perceive
ideal geometrical shapes with the eyes of the mind alone. But despite a degree of affinity between
Plato’s views and Descartes’s, Descartes likely had a different point in
mind. When I remember something there
is a sense in which it is up to me: I can choose which of my memories to
remember and when to remember it. But
there is also a sense in which remembering is not up to me: I cannot change
the content of my memories, but can only remember things that actually
happened to me in the past. Other things can be imagined, but not
remembered. Descartes’s point was
similar, though not identical. While I
can imagine ideas of this or that geometrical shape at will, and make them
come or go, or exchange them for others, any particular shape I choose to
imagine is imagined under constraints that are beyond my control, much as the
content of my memories is beyond my control.
There are properties of geometrical shapes that I cannot alter. A triangle must have its longest side
opposite its largest angle, and must have internal angles that are equal to
two right angles. A cube must have six
faces. Given four equidistant points,
there cannot be anywhere where a fifth point could be placed that is
equidistant from each of the other four.
Some of these features may be features that I have never used my
understanding to clearly and distinctly perceive, but when I do once perceive
them, even for the first time, I do not have the feeling that I have put them
into the triangle, but instead think that the feature was present, unnoticed,
in all the triangles I thought of in the past. This is another sense in which I seem to be
“remembering” rather than perceiving these features. Of course, this raises a question: might I
really be remembering? That is, might
I originally have obtained my ideas of extension and shapes by sensing
extended and shaped objects, so that the reason why these ideas appear a
certain way to me now is just that I am remembering them as they originally
were? Descartes rejected this
possibility on the ground that we are able to imagine geometrical shapes we
are sure we have never seen before, but these shapes, too, have certain
essential features that we cannot alter. These reflections led Descartes to conclude
that, despite the fact that there may be no extended things existing outside
of us, our ideas of these things have a real and unchangeable nature that is
independent of us. While I can make my
ideas of triangles come and go, I cannot make an idea of a right angle
triangle with a hypotenuse that is greater or lesser in length than the
square root of the sum of the squares of the lengths of its sides. This feature of triangles is not up to me
to determine and beyond my control to alter.
Consequently, the Pythagorean theorem, which expresses this feature,
states something real and true and not merely something fanciful. And the same may be said of all the other
propositions of geometry and arithmetic.
But nothingness or a privation of reality cannot constrain my thought
to take on a certain form. Only
something real can do that. Thus, our
ideas of extension and its modes must be ideas of something that is positive
and real. They cannot be materially
false ideas of nothing or of a privation of reality. Again, this is not to say that extended things
must exist. Though the ideas of
extension are of a quality that is positive and real, it remains a question
whether there is anything that possesses this positive quality. We can, however, affirm that whatever we
learn through geometry about extension has the status of a general rule that
would have to be obeyed by extended objects if they were to exist.
However, it is only in Meditations VI
that considerations are brought forward to establish that extended things are
more than merely possible in conformity with these general rules. b. The ontological argument for the existence
of God. At this point,
Descartes paused to observe that there is one case where inspection of the
content of ideas can establish the actual existence of an object
corresponding to that idea. This is
the case of the idea of God. Our idea
of God is the idea of a supremely perfect being. But, according to Descartes, existence adds
to the perfection of a thing. This is
proven by the fact that, if you were offered a choice between having ten
actually existing dollars and ten imaginary dollars, you would choose the
actually existing ones. Your
preference for the actually existing ones proves that existence adds to the
perfection of a thing. Consequently,
were God to lack existence, God would be less than supremely perfect, which
is contrary to what the idea of God tells us.
We must conclude, therefore, that our idea of God is the idea of an
existing thing. Existence is as
inseparable from God as having internal angles equal to two right angles is
from a triangle, and is demonstrable in the same way: by clearly and
distinctly perceiving what is contained in the idea of the thing. Were God not to exist, our idea of God
would be false (since it represents God as existing), and we know that
nothing that we clearly and distinctly perceive could turn out to be false. (For that it is worth, the example of the ten
dollars is actually due to Immanuel Kant, who spoke of thalers (“tolers”), a
silver coin in use at the time from which the name “dollar” is derived. Kant, who was no supporter of Descartes’s
argument, used the example to express an anti-Cartesian point: that ten real
dollars do not contain one penny more than ten imaginary dollars, and so are not any more perfect.) Descartes proceeded to raise and answer three
objections to this argument. The first
is that, as he put it, questions concerning the existence of a thing are
distinct from questions concerning its “essence” or definition. We can define an idea as we will — or as we
clearly and distinctly perceive it to be — but it still remains a question whether
anything exists that corresponds to the idea as thus defined. When defining a thing we list the real
features or qualities that it has to possess in order to be that sort of
thing. But many philosophers have
maintained that existence is not a real feature or quality. Saying that something exists does not add
to the reality of the thing being defined or make it a different kind of
thing, as if an existing dragon were a different species of animal from a
non-existing dragon, the way a rational animal is a different species from an
irrational animal. When we say that
something exists we are merely adding the information that there is an object
in the world that corresponds to the idea; we are not listing any real
quality of the idea itself. As Kant
later to put it, ten existing dollars does not contain one penny more than
ten possible dollars. If we prefer the
one to the other, it is not because the one is greater or more perfect in any
way, but only because we know that the one has a partner in the external
world as well as being a mere idea in the mind. Descartes’s response to this objection was to
dig in his heels and insist that existence nonetheless adds to the perfection
of a thing. We only think it does not because
in most (and perhaps all) other cases existence is not part of the essence of
the thing. This has made us accustomed
to think that existence is not a perfection.
But we discover the error of this customary impulse when we consider
the idea of an all perfect being, since in that case a clear and distinct
perception on the part of the understanding compels the will to assert that a
supremely perfect being would be less than perfect were it not to exist. A second objection is that our thoughts impose
no necessity on things. So simply
because we conceive of a certain idea, it does not follow that anything must
exist corresponding to that idea. As
one of the objectors to an earlier version of Descartes’s argument put it, I
can conceive of a supremely perfect island.
But it does not follow that any island has to exist. Descartes’s response to this objection was to
admit that our thought imposes no necessity on things, and that simply
because we do conceive of something
as being a certain way, it does not follow that anything must exist that
actually is that way. But, he
proceeded to observe, in the case of the idea of a supremely perfect being I must conceive of existence as one of
the attributes of the being. This is
not something that is up to my choice, just is it is not up to my choice to
conceive of a triangle that has internal angles that sum to anything other
than two right angles. In both of
these cases, far from it being the case that my thought imposes a necessity
on things, the nature of the things imposes a necessity on my thought, which
compels my idea to take on a certain form. A further problem with the counterexample of
the supremely perfect island is that conception is not just arbitrarily
concocted but even self-contradictory.
To be an island is to be surrounded by water, which means being only
finitely extended. That already means
being less than supremely perfect. An
island is also just a clump of earth, lacking powers of vegetation, growth,
nutrition, reproduction, self-movement, sensation, reasoning, memory,
etc. So there are a great many ways in
which an island is imperfect. That
makes the idea of a supremely perfect island maximally confused — self-contradictory. If we modify the example by adding
perfections to the idea of the island, it stops being an idea of an island
and becomes the idea of God. It is
only when we consider the idea of a being that is supremely perfect (and there can only be one such being) that we
find a reason to assert existence. In
all other cases, where the thing we conceive is thought to lack some
perfection or other, a further reason would have to be given why that being
should not also lack the perfection of existence. A final objection is that the idea of a
supremely perfect being might be like the idea of a supremely perfect island
— it might be an obscure or incoherent idea to which nothing can
correspond. Existence only follows
from the idea of God because we have verbally included something in the idea (supreme
perfection) that necessarily entails existence. But we need not and perhaps ought not to
have defined the idea that way.
Similarly, were we to define a four sided figure as a figure that can
be inscribed in a circle, it would necessarily follow from the definition
that a rhombus must be a figure that can be inscribed in a circle. But that is wrong, which goes to show that
the idea was obscure and incorrectly formed. Descartes’s response to this objection was to
remark that when I form an obscure or incoherent idea, I am not constrained
to form the idea in any particular way.
But while it is up to me to think of a supremely perfect being or not,
when I do think of this idea, I am constrained to conceive of it as an idea
of something that exists. Similarly,
while it is up to me to think of a triangle or not, when I do think of this
idea, I am constrained to conceive of it as an idea of something that has
internal angles equal to two right angles.
In the case of the four sided figures, I am so far from being
constrained to conceive them as all being such that they can be inscribed in
a circle that I am on the contrary easily able to conceive counterexamples to
that claim, and so clearly and distinctly conceive that it must be false. It seems strange that Descartes should have
suddenly detoured to offer yet another argument, his third, for the existence
of God. One consideration that may
have motivated him to return to this topic is that his proofs of God’s
existence in Meditations III are
proofs of a quite different sort from the one he offered here. The Meditations III proofs are what can be
called a posteriori proofs or
proofs “after the fact.” In an a posteriori proof, the
conclusion is established only after the fact of the existence of some other
thing has first been established. Thus,
in Meditations III, Descartes first
needed to establish the existence of the idea of God, or the existence of
himself as a thinking thing that has an idea of God, before he could prove
that God must exist. The Meditations V proof, in contrast, like
all the proofs in geometry, is an a priori
proof or a proof “in advance of the facts.”
In an a priori proof
one does not first need to establish that anything else exists. One proceeds merely by analyzing or
defining or, as Descartes would have preferred to put it, clearly and
distinctly perceiving what is contained in the idea of a thing, and the
analysis alone reveals the truth one is seeking. This is of course the method of proof that Meditations IV recommends as the way
to uncover the truth, and Descartes may have been concerned to show that such
an important proposition as that of the existence of God can itself be proven
by the method, and not merely by a posteriori
means. He may also have wanted to
insinuate that whatever doubts might be raised concerning his arguments for
the existence of God in Meditations
III, anyone who is willing to accept proofs in geometry ought by the same
token to accept this proof, which is based the same kind of analysis of
ideas. c. The rehabilitation of the mathematical
sciences. Indeed, Descartes took
the proof of God’s existence to not only be as certain as any other proof in
geometry or mathematics, but to be foundational for all of those proofs. We might think that, if we know that the ideas
of extension and its modes are real and true, then, whatever we can clearly
and distinctly perceive about those ideas, as codified in the mathematical
sciences, would constitute an independent body of absolutely certain
truths. But Descartes claimed that the
proof of God’s existence underwrites our certainty of all other demonstrative
proofs in the mathematical sciences, so that were this important point not
established in advance our certainty would be limited and incomplete. To justify this claim, Descartes reviewed what
he had established over the course of Meditations
III-IV. The certainty produced by
clear and distinct perception is transitory.
It exists only for as long as the understanding is actually engaged in
contemplating the particular ideas involved in the judgment in question. Under those conditions the understanding
determines the will and we must judge accordingly. But when the understanding turns to
contemplate other things, the will is no longer determined. In the absence of a continued determination
of the will, and in the absence of a proof of the existence of God, doubts
can creep in. We can note that we have
made mistakes in calculation in the past and worry that we might just have
made another one. Or we can worry that
an evil genius might be deceiving us.
Admittedly, these worries can be removed by returning to clearly and
distinctly perceive the relation between the ideas involved in the judgment,
which will produce an irresistible conviction, given that the understanding
determines the will. However, this
puts us in a difficult situation. The
only way to preserve certainty is to constantly return to old proofs and
contemplate them again, and the instant we turn to something else, doubt
returns. Consequently, we end up being
able to be certain of only a very few things: as many as we can manage to
clearly and distinctly perceive at once.
Worse, anything that can only be known by means of a long proof,
requiring many steps or an appeal back to results established earlier, ends
up being indemonstrable. No complex
proposition is provable. Descartes maintained that the proof of the
existence of God removes us from this predicament. Once we have clearly and distinctly
perceived that God exists, and have understood how far error on our part is
compatible with God’s nature, we appreciate that God would not permit us to
be mistaken about what we clearly and distinctly perceive, and would not
allow any other being to trick us into thinking that we clearly and
distinctly perceive something when we do not in fact do so. God may allow other beings to tempt us into
error, but never about things that are clearly and distinctly perceived. And we ourselves may occasionally make
errors in calculation, but as long as we are careful to frequently check our
proofs we can trust that we will uncover the mistake. According to Descartes, this removes our
doubts and allows us to be certain of the conclusions of demonstrations, even
when we are not currently engaged in clearly and distinctly perceiving
them. All we need to do is remember
that we (repeatedly) clearly and distinctly perceived these matters in the
past. We might wonder about the efficacy of this
solution. My certainty about some
truth that I do not now clearly and distinctly perceive, such as that 786 x
13 = 10,218, is only as good as my memory that I did previously clearly and
distinctly perceive this conclusion.
But remembering that one has clearly and distinctly perceived
something is not the same thing as clearly and distinctly perceiving it. Such memories can be mistaken. Indeed, we might speculate that when we
make mistakes in simple sums, such as supposing that 7+5=13, this is always
because we misremember what we clearly and distinctly perceived to be the case
at some time in the past. Were Descartes
to take things so far as to say that the goodness of God would never allow my
memory to mislead me about what I have clearly and distinctly perceived he
would be making a claim that is hard to accept, because I now remember that
my memory has deceived me about arithmetical sums. If I am wrong about that, then my memory is
now deceiving me. If I am not wrong, then it has indeed
deceived me in the past. Either way it
seems that my memory is untrustworthy. A possible answer to this objection (though
not one that Descartes himself offered in Meditations
V) would appeal to the fourth rule of the method of Discourse II. Recall that
rule four stipulates that we must make frequent reviews of our work. Remembering having performed a proof is not
enough. We need to go back and perform
the proof repeatedly. This could
conceivably involve writing parts of the proof down and then reviewing those
notes, considering them as a list of what steps we performed in what order. If, after repeated runs through the proof,
we remain unable to discover any error, then we can recall (or prove once
again) that God would not allow us to be deceived about any matter without
having given us some capacity to discover our error. But beyond reviewing a proof over and over
again, and using notes and other aids to our memory, there is nothing more we
can do to assure ourselves of the correctness of a proof. So were we to still be convinced after
frequent reviews of the proof, we can be assured that we would have done all
we could to uncover a mistake in calculation or an error in remembering
earlier steps, and we could think that the goodness of God would guarantee
that the proof must be correct. (For
an attempt to defend Descartes along these lines see John Cottingham, Descartes [Oxford: Blackwell, 1986],
71-72.) We might object that even if I make frequent
reviews of my work, I still need to remember that I did so, and even if I
take down notes, I need to remember that those notes are mine. I could merely dream that I performed the
proof over and over again when in fact I never did any such thing, and if I
am now dreaming when I look at my notes, those notes may not actually record
a previous effort at doing the proof. Descartes’s answer to this objection would
probably be that, having satisfied myself that God exists and is no deceiver
(and only because I have
satisfied myself of this), I can lay these sorts of extravagant doubts to
rest. God would simply not allow me to
be deceived about matters in which there is no hope of uncovering my error. We might rest uneasy with this, and worry that
even if there is no deceiver and even if my memory is generally reliable
about certain sorts of things, it is far from being beyond all possibility
that I might be now asleep and dreaming, utterly convinced that I repeatedly
intuited results I never actually considered.
But Descartes would be complacent about this and advise us to rest
assured that, God being no deceiver, we will sooner or later discover our
error if in fact we are making one. We
will wake up and realize we were just dreaming. It would do well, in this context, to look
ahead to the last sentence of the Meditations. “But because the need to get things done
does not always permit us the leisure for such a careful inquiry, we must
confess that the life of man is apt to commit errors regarding particular
things, and we must acknowledge the infirmity of our nature.” A great deal of emphasis is often placed on
the claim that Descartes was an arch-foundationalist, who sought to rest all
knowledge on a basis of absolute certainty.
As a matter of fact (and as will be seen in more detail when we turn
to Cartesian science) this picture is seriously mistaken. Descartes’s Meditations were meditations on first philosophy. (“First
philosophy” is another name for metaphysics or the science that precedes
physics.) The quest for certainty was
a quest that Descartes engaged in only for a limited time and for a limited
reason. He wanted to be sure of the
most general principles. But, having established
general principles, he was content to be less than certain about specifics
and particular things. Indeed, on
certain matters he was convinced that certainty is impossible and that we
will never be able to do more than make conjectures. On the reading I would favour, Descartes
would not have been distressed by the possibility that we might not be
certain of the result of any complex demonstration because it would involve a
reliance on memory of what has been clearly and distinctly perceived in the
past. His response to such a situation
would have been to say that in such cases we simply do the best we can and
hope we get it right. We do not need
to be absolutely certain that we have not been deceived. The fallible certainty that comes from remembering
having reviewed the proof a number of times over is good enough. It is sufficient that we be absolutely
certain just of the most fundamental things — indeed, just that we be assured
that we could not be systematically deceived or mistaken about even the
simplest and most fundamental things, such as the existence of God and the
reality of extension. ESSAY
QUESTIONS AND RESEARCH PROJECTS
1. Do a comparative study
of the employment of the notions of clarity/obscurity and
distinctness/confusion by philosophers of the 17th and 18th centuries (in
addition to Descartes, important figures to consider include Hobbes, Locke,
Spinoza, and Leibniz, as well as the authors of seventeenth century logic
textbooks that discuss these notions).
Attempt to identify any significant divergences in the way these
notions are understood. Look also at
accounts of immediate or intuitive knowledge as they appear in the works of
these authors and attempt to ascertain any connection there might be between
the notion of clear and distinct perception and the notion of intuitive
knowledge. Is it the case, for
example, that clear and distinct perception simply consists in seeing one
idea analytically contained inside of another and that it is this direct
perception of containment that constitutes intuitive knowledge?
2. Assess the adequacy of
Descartes’s attempt to defend his ontological argument for the existence of
God against the objections he himself raises to that argument. Consider whether there are any other, more
serious objections he fails to consider and then consider whether he could
also answer those objections.
3. Based on a survey of
Descartes’s remarks in the Meditations,
Replies to objections to the
Meditations, Principles of
philosophy Part I, and in his correspondence, try to determine exactly
what his position was on why we need to be assured of the existence of God in
order to know other things, and what those other things are. Do I need to be assured of the existence of
God before I can know any of the things I clearly and distinctly perceive,
including my own existence, or just some of these things? Or is it rather the case that I need to be
assured of the existence of God before Ie can be assured of the conclusion of
a demonstration, but not of the truth of those things that I clearly and
distinctly perceive without the assistance of a demonstration? Or is it just the case that Ie only need to
be assured of the existence of God before I can be assured of the conclusions
of demonstrations I am not now contemplating, but only remember having
performed and clearly and distinctly perceived?
4. How serious is the
following objection: At the close of Meditations V, Descartes claimed that
a proof of the existence of God puts us in a position to rely on the memory
of having clearly and distinctly perceived or demonstrated a truth. But, unlike clear and distinct perception,
which is an act of the understanding that can arguably be considered to be
infallible, remembering is an act of memory, and we know from experience that
our memories are unreliable and can often perceive us. Moreover, the argument of Meditations IV does nothing to
establish the reliability of memory (it only establishes the reliability of
clear and distinct perception). Since
we have good reason to doubt the reliability of memory, we still cannot rely
on the truth of demonstrations that we only remember having performed,
Descartes’s proof of the existence of God notwithstanding. Could Descartes have replied to this objection? If so, how?
If not, might he still have been able to go on to say everything he
did in Meditations VI or would his
other conclusions be put in jeopardy?
5. Does anything that
Descartes had to say in Meditations
V help to answer the objection that there is a circularity in his demonstration
of the existence of God in Meditations
III?
6. How does the Meditations V argument for the
existence of God differ from the Meditations
III argument? Why is the Meditations V argument necessary? Might it just as well have been given in Meditations III or is there something
about the Meditations V argument
that makes it dependent on the results of Meditations
IV? Is the Meditations III argument any less dependent on the conclusions of
Meditations IV than the Meditations V argument? |