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Descarte`s Cartesian Doubt


In his first meditation, Descartes sets out with amazing clarity and persistence
to clear himself of every false idea that he has acquired previous to this, and
determine what he truly knows. To rid him of these "rotten apples" he
has developed a method of doubt with a goal to construct a set of beliefs on
foundations which are indubitable. On these foundations, Descartes applies three
levels of skepticism, which in turn, generate three levels at which our thoughts
may be deceived by error. Descartes states quite explicitly in the synopsis,
that we can doubt all things which are material as long as "we have no
foundations for the sciences other than those which we have had up till
now"(synopsis:12). This skepticism also implies that doubt can free us from
prejudices, enabling the mind to escape the deception of the senses, and
possibly discover a truth which is beyond doubt. The first and main deception in

Descartes opinion has evolved from sense perception "What ever I have up
till now accepted as most true I have acquired either from the senses or through
the sense. But from time to time I have found that the senses deceive, and it is
prudent never to trust completely those who have deceived us even
once"(1:18[13]). At the root of our beliefs, Descartes argues, lie the
experiences we gain from our senses, because these are sometimes mistaken, as in
the case of mirages or objects which appear small in the distance, and because
of this he will now forfeit all of his most reliable information . More
importantly it may be to follow in the steps of Plato and require knowledge that
is certain and absolute ( Prado 1992 ). This argument consists of four main
premises: 1. All that he has accepted as true up to this point, he has acquired
by the senses or Cartesian Doubt 3 through the senses; 2. but on occasion these
senses have been deceptive. 3. It is wise not to trust anything that has been
deceiving in the past 4. Therefore, it is possible to be mistaken about
everything. In premise one his beliefs are derived from the senses, such as he
sees that he has a paper in his hand and concludes that it is a paper, and what
is meant by through the senses, is that his beliefs may have been based on
others sense experience. All Descartes requires for the second premise is the
possibility that he may have been deceived, for if he cannot decide which is
wrong, than he must not have any knowledge. This leads to the third premise
where it seems at least reasonable to assume, that if one has been deceived
previously, there is no absolute assurance that it is presently correct.

Therefore, there is a chance of being deceived about everything. But many
critics will argue that several of these false percepts can be corrected by
means of alternative senses, such as he bent stick in water example. Although
our sight may be tricked into thinking that the mirage exists, by using the
sense of touch we can correct this falseness, and uncover what truly exists.

Descartes does retreat, and assess the damage from his first level by saying,
"there are many other beliefs about which doubt is quite impossible, even
though they are derived from the senses-for example, that I am here, sitting by
the fire, wearing a winter dressing gown.." (1:18[12]). Here even he
objects to the validity of his argument, even if he could be deceived about
anything he perceives, this does not mean that he is deceived about everything.

Just because his senses are unreliable at times is not proof enough that
everything in the world is false (Williams 1991). In addition to being
delusional, Descartes believes we can be tricked by madness or insanity. Since
those who are insane may interpret things detached from reality by means of
their senses, " how could it be denied that these hands or this whole body
are mine? Unless perhaps I were to liken myself to madmen, whose brains are so
damaged by the persistent vapours of melancholia" (1:19 [13]), they in fact
believe these percepts to be true. Though Descartes does go on to say "such
people are insane, and I would be thought equally mad if I took anything from
them as a model for myself", and continues by likening the dreams he has to
the experiences a madman faces when awake. From here Descartes makes a stronger
argument for calling into question his common sense beliefs, the possibility
that he might be dreaming, that every emotion and every sense perception appears
to him only in a dream. Since there is always a possibility that we may in fact
be dreaming, this hypothesis is done to provoke his faith in reality and the
senses, to get the absolute certainty of how things may appear or feel (Prado

1992). His view on this is taken from the fact that when dreaming, the same
types of mental states and feelings are present as when we are awake, "How
often, asleep at night , I am convinced of just such a familiar event-that I am
here in my dressing-gown, sitting by the fire- when in fact I am lying undressed
in bed" (1:19[13]). Since there is no absolute way in determining the
waking state from the dreaming state, when it comes to sense experience, we are
no better off awake than asleep. Therefore our judgment must be suspended even
when we are sure that our state is that of waking because "we clearly have
no reason to believe that effects resemble their causes in the waking state,
since they clearly do not in the dreaming state" (Prado, 1992). The only
way we can avoid the suspension of judgement is only if we have a standard to
determine where the truth exists (Williams 1986). To use the conflict of the
stick being bent in water, what sense is it that we should believe, when we have
no tool to decipher the truth? Thus, the suspension of truth works for the doubt
of he senses as well. The reason why doubting the senses is not enough to base
an entirely new set of ideas, is due to the fact that it does not call into
question all of ones common sense beliefs, for the representations found in
dreams are derived from real objects, although possibly arranged in a different
way. The thoughts and feelings of a dream are real, they are the same thoughts
and feelings that occur every day in the waking state. To be afraid during a
dream is the same feeling experienced if . It is due to the similarities in
feelings and thought between dreaming and waking, that Descartes is able to find
ground for doubt, "there are never any sure signs by means of which being
awake can be distinguished from being asleep" (1:19[13]). This than leads
to the eternal skeptical question : "How can I tell whether at this moment

I am awake or asleep?" (Malcolm, 1967). If we take any series of thoughts,
emotions or feelings, it is possible that the same series can occur while
dreaming or awake. Thus, we can never be absolutely clear on whether what we are
experiencing at that exact moment in time is a dream, or that of a waking state.

Though Prado (1992) insists that Descartes states in the sixth meditation, that
temporal coherence allows us to decipher between the waking and dreaming states.

The aim here then would be to prove that there is nothing in the waking state to
confirm the accuracy of sense experience. The fact that at any given moment our
current state could change drastically and render the previous state an
illusion, may be enough to support his skeptical nature on thus, his Cartesian

Doubt 6 second level of doubt (Williams 1991). As long as Descartes second level
of doubt is accepted, we are able to continue on to his third level of doubt, or
what is known as hyperbolical doubt. Descartes considers our beliefs within
dreams when he says that some beliefs remain indubitable while others are swept
away by imagination. Such things as the laws of physics can be broken within
dreams, where other concepts such as arithmetic or geometry remain unchanged:
physics, astronomy, medicine and all other disciplines which depend on the study
of composite things, are doubtful; while arithmetic, geometry ans other subjects
of this kind, which deal only with the simplest and most general things,
regardless of whether they really exist in nature or not, contain something
certain and indubitable. (1:20[14]) He decides that certain things which are
accepted universally, such as mathematics, are irrefutable. The dream hypothesis
is not enough to doubt such things as mathematics, as we may be dreaming that
there appears a square in front of us, but we cannot doubt our reason, such that
it has four sides, or that there is only one square that we see and not two or
three. He moves on to discuss the origins of our beliefs, and the role of an
omnipotent God. He believes that there is a God, due to the fact that this idea
of God is "firmly rooted" in his mind, and he also believes that this
omnipotent God would not deceive him since he is "supremely good". He
examines the assumption that God is perfect and omnipotent, and therefore the
source for all of our thoughts and ideas. Since Descartes is abandoning all of
his old beliefs, this would suggest that God tried to deceive him. He wonders
why such a perfect God would deceive him, and figures it must be doubtful.

Cartesian Doubt 7 Now Descartes imagines that God is not the one who is
deceiving him, but none other than a malevolent demon, who with deceitful power,
implants false beliefs, " I will suppose therefore that not God, who is
supremely good and the source of truth, but rather some malicious demon of the
utmost power and cunning has employed all his energies in order to deceive
me" (1:22[15]). When determining what is open to doubt, Descartes' evil
demon hypothesis conveniently creates a being who is omnipotent and who uses the
power solely to deceive. What Descartes achieves is making problematic a host of
ideas he entertains as products of reason , opposed to products of the senses,
which the dream hypothesis takes care of (Prado 1992). Although L.G. Miller
(1992) suggests that the propositions of mathematics survive the perception and
dream arguments, but only to be unsettled by the deceiver God hypothesis,
"Could not an all-powerful demon make me believe those propositions are
true when, as a matter of fact, they are not?" The deceiver God does not
succeed if the person accepts that the reality he lives in is true. However,
with the rise of skepticism and questioning the veracity of whether the world we
live in is accurate or not, perhaps the demon has won after all. Descartes then
leaves the first meditation in a state of confusion. He knows at least how
things seem to appear to him, even if he has no idea how they really are "I
am like a prisoner who is enjoying an imaginary freedom while asleep, he dreads
being woken up, and goes along with the pleasant as long as he
can"(1:23[15). Descartes clearly refocused metaphysical thinking into the
physical world, by turning it toward the natural world. His basic structure has
four uses of doubt, firstly to free us from preconceived opinions or prejudice,
the second is to lead the mind away from the senses, the Cartesian Doubt 8 third
use of doubt makes it impossible to have any further doubts about those things
which alter such an "extensive doubt" and are discovered to be true,
while the fourth is to provide us with an understanding of what certainty is.

Descartes methodological doubt can be defined as foundationalism, which is the
belief that knowledge is formed on different levels, much like an inverted
pyramid. Such that, complex beliefs come first, then beneath that are simpler
beliefs and beneath them are the simplest beliefs. Foundationalism requires not
only this hierarchy effect, but also that nothing is accepted as knowledge until
we know upon what it is based (Prado 1992). In summary of what the three main
arguments undermine, the argument from the illusion or deceptiveness of the
senses undermines ordinary sense perception. Undermining ordinary sense
perception and scientific observation as well as the more theoretical parts of
the physical sciences and hence these sciences as a whole is the dream
hypothesis, while the deceiver God hypothesis undermines the pure mathematical
sciences such as arithmetic and geometry. Descartes' metaphysical doubt
emphasizes purging the old falsehoods and buildings up again from the bedrock of
the indubitable of our existence as thinkers. Whether or not the extensiveness
of such skepticism used by Descartes is necessary, remains open for doubt. But
for one to gain any knowledge what so ever, they must be capable of doubting at
some point or another, rather than accepting all that they may hear. It would be
extremely credulous and naive to never doubt or question it is only natural to
doubt and challenge that which one does not believe, and to a certain extent,
being the natural extent, it is useful and necessary, "When Descartes
begins to doubt in an epistemological mode, he cannot stop short of doubting
whether Cartesian Doubt 9 he himself exists as a doubter" (Prado 1992)..

Perhaps, when the poet Charles Bukowski said "the more crap you believe,
the better off you are," he realized that such an extensive doubt can be
harmful to the majority of people, because they are in fact "better
off" believing in their senses, their God, and their ability to determine
whether they are sleeping or awake. It is possible that it may be beneficial to
live and die being deceived, and be ignorant to that deception, than to live and
die searching for truth where truth may not be found, for the true determinant
to whether such an extensive skepticism is beneficial or necessary depends on
the individual. Neither Descartes nor Bukowski can speak for anyone other than
themselves. In his first meditation, Descartes sets out with amazing clarity and
persistence to clear himself of every false idea that he has acquired previous
to this, and determine what he truly knows. To rid him of these "rotten
apples" he has developed a method of doubt with a goal to construct a set
of beliefs on foundations which are indubitable. On these foundations, Descartes
applies three levels of skepticism, which in turn, generate three levels at
which our thoughts may be deceived by error. Descartes states quite explicitly
in the synopsis, that we can doubt all things which are material as long as
"we have no foundations for the sciences other than those which we have had
up till now"(synopsis:12). This skepticism also implies that doubt can free
us from prejudices, enabling the mind to escape the deception of the senses, and
possibly discover a truth which is beyond doubt. The first and main deception in

Descartes opinion has evolved from sense perception "What ever I have up
till now accepted as most true I have acquired either from the senses or through
the sense. But from time to time I have found that the senses deceive, and it is
prudent never to trust completely those who have deceived us even
once"(1:18[13]). At the root of our beliefs, Descartes argues, lie the
experiences we gain from our senses, because these are sometimes mistaken, as in
the case of mirages or objects which appear small in the distance, and because
of this he will now forfeit all of his most reliable information . More
importantly it may be to follow in the steps of Plato and require knowledge that
is certain and absolute ( Prado 1992 ). This argument consists of four main
premises: 1. All that he has accepted as true up to this point, he has acquired
by the senses or Cartesian Doubt 3 through the senses; 2. but on occasion these
senses have been deceptive. 3. It is wise not to trust anything that has been
deceiving in the past 4. Therefore, it is possible to be mistaken about
everything. In premise one his beliefs are derived from the senses, such as he
sees that he has a paper in his hand and concludes that it is a paper, and what
is meant by through the senses, is that his beliefs may have been based on
others sense experience. All Descartes requires for the second premise is the
possibility that he may have been deceived, for if he cannot decide which is
wrong, than he must not have any knowledge. This leads to the third premise
where it seems at least reasonable to assume, that if one has been deceived
previously, there is no absolute assurance that it is presently correct.

Therefore, there is a chance of being deceived about everything. But many
critics will argue that several of these false percepts can be corrected by
means of alternative senses, such as he bent stick in water example. Although
our sight may be tricked into thinking that the mirage exists, by using the
sense of touch we can correct this falseness, and uncover what truly exists.

Descartes does retreat, and assess the damage from his first level by saying,
"there are many other beliefs about which doubt is quite impossible, even
though they are derived from the senses-for example, that I am here, sitting by
the fire, wearing a winter dressing gown.." (1:18[12]). Here even he
objects to the validity of his argument, even if he could be deceived about
anything he perceives, this does not mean that he is deceived about everything.

Just because his senses are unreliable at times is not proof enough that
everything in the world is false (Williams 1991). Cartesian Doubt 4 In addition
to being delusional, Descartes believes we can be tricked by madness or
insanity. Since those who are insane may interpret things detached from reality
by means of their senses, " how could it be denied that these hands or this
whole body are mine? Unless perhaps I were to liken myself to madmen, whose
brains are so damaged by the persistent vapours of melancholia" (1:19
[13]), they in fact believe these percepts to be true. Though Descartes does go
on to say "such people are insane, and I would be thought equally mad if I
took anything from them as a model for myself", and continues by likening
the dreams he has to the experiences a madman faces when awake. From here

Descartes makes a stronger argument for calling into question his common sense
beliefs, the possibility that he might be dreaming, that every emotion and every
sense perception appears to him only in a dream. Since there is always a
possibility that we may in fact be dreaming, this hypothesis is done to provoke
his faith in reality and the senses, to get the absolute certainty of how things
may appear or feel (Prado 1992). His view on this is taken from the fact that
when dreaming, the same types of mental states and feelings are present as when
we are awake, "How often, asleep at night , I am convinced of just such a
familiar event-that I am here in my dressing-gown, sitting by the fire- when in
fact I am lying undressed in bed" (1:19[13]). Since there is no absolute
way in determining the waking state from the dreaming state, when it comes to
sense experience, we are no better off awake than asleep. Therefore our judgment
must be suspended even when we are sure that our state is that of waking because
"we clearly have no reason to believe that effects resemble their causes in
the waking state, since they clearly do not in the dreaming state" (Prado,

1992). Cartesian Doubt 5 The only way we can avoid the suspension of judgement
is only if we have a standard to determine where the truth exists (Williams

1986). To use the conflict of the stick being bent in water, what sense is it
that we should believe, when we have no tool to decipher the truth? Thus, the
suspension of truth works for the doubt of the senses as well. The reason why
doubting the senses is not enough to base an entirely new set of ideas, is due
to the fact that it does not call into question all of ones common sense
beliefs, for the representations found in dreams are derived from real objects,
although possibly arranged in a different way. The thoughts and feelings of a
dream are real, they are the same thoughts and feelings that occur every day in
the waking state. To be afraid during a dream is the same feeling experienced if
. It is due to the similarities in feelings and thought between dreaming and
waking, that Descartes is able to find ground for doubt, "there are never
any sure signs by means of which being awake can be distinguished from being
asleep" (1:19[13]). This than leads to the eternal skeptical question :
"How can I tell whether at this moment I am awake or asleep?"
(Malcolm, 1967). If we take any series of thoughts, emotions or feelings, it is
possible that the same series can occur while dreaming or awake. Thus, we can
never be absolutely clear on whether what we are experiencing at that exact
moment in time is a dream, or that of a waking state. Though Prado (1992)
insists that Descartes states in the sixth meditation, that temporal coherence
allows us to decipher between the waking and dreaming states. The aim here then
would be to prove that there is nothing in the waking state to confirm the
accuracy of sense experience. The fact that at any given moment our current
state could change drastically and render the previous state an illusion, may be
enough to support his skeptical nature on thus, his Cartesian Doubt 6 second
level of doubt (Williams 1991). As long as Descartes second level of doubt is
accepted, we are able to continue on to his third level of doubt, or what is
known as hyperbolical doubt. Descartes considers our beliefs within dreams when
he says that some beliefs remain indubitable while others are swept away by
imagination. Such things as the laws of physics can be broken within dreams,
where other concepts such as arithmetic or geometry remain unchanged: physics,
astronomy, medicine and all other disciplines which depend on the study of
composite things, are doubtful; while arithmetic, geometry ans other subjects of
this kind, which deal only with the simplest and most general things, regardless
of whether they really exist in nature or not, contain something certain and
indubitable. (1:20[14]) He decides that certain things which are accepted
universally, such as mathematics, are irrefutable. The dream hypothesis is not
enough to doubt such things as mathematics, as we may be dreaming that there
appears a square in front of us, but we cannot doubt our reason, such that it
has four sides, or that there is only one square that we see and not two or
three. He moves on to discuss the origins of our beliefs, and the role of an
omnipotent God. He believes that there is a God, due to the fact that this idea
of God is "firmly rooted" in his mind, and he also believes that this
omnipotent God would not deceive him since he is "supremely good". He
examines the assumption that God is perfect and omnipotent, and therefore the
source for all of our thoughts and ideas. Since Descartes is abandoning all of
his old beliefs, this would suggest that God tried to deceive him. He wonders
why such a perfect God would deceive him, and figures it must be doubtful.

Cartesian Doubt 7 Now Descartes imagines that God is not the one who is
deceiving him, but none other than a malevolent demon, who with deceitful power,
implants false beliefs, " I will suppose therefore that not God, who is
supremely good and the source of truth, but rather some malicious demon of the
utmost power and cunning has employed all his energies in order to deceive
me" (1:22[15]). When determining what is open to doubt, Descartes' evil
demon hypothesis conveniently creates a being who is omnipotent and who uses the
power solely to deceive. What Descartes achieves is making problematic a host of
ideas he entertains as products of reason , opposed to products of the senses,
which the dream hypothesis takes care of (Prado 1992). Although L.G. Miller
(1992) suggests that the propositions of mathematics survive the perception and
dream arguments, but only to be unsettled by the deceiver God hypothesis,
"Could not an all-powerful demon make me believe those propositions are
true when, as a matter of fact, they are not?" The deceiver God does not
succeed if the person accepts that the reality he lives in is true. However,
with the rise of skepticism and questioning the veracity of whether the world we
live in is accurate or not, perhaps the demon has won after all. Descartes then
leaves the first meditation in a state of confusion. He knows at least how
things seem to appear to him, even if he has no idea how they really are "I
am like a prisoner who is enjoying an imaginary freedom while asleep, he dreads
being woken up, and goes along with the pleasant as long as he
can"(1:23[15). Descartes clearly refocused metaphysical thinking into the
physical world, by turning it toward the natural world. His basic structure has
four uses of doubt, firstly to free us from preconceived opinions or prejudice,
the second is to lead the mind away from the senses, the Cartesian Doubt 8 third
use of doubt makes it impossible to have any further doubts about those things
which alter such an "extensive doubt" and are discovered to be true,
while the fourth is to provide us with an understanding of what certainty is.

Descartes methodological doubt can be defined as foundationalism, which is the
belief that knowledge is formed on different levels, much like an inverted
pyramid. Such that, complex beliefs come first, then beneath that are simpler
beliefs and beneath them are the simplest beliefs. Foundationalism requires not
only this hierarchy effect, but also that nothing is accepted as knowledge until
we know upon what it is based (Prado 1992). In summary of what the three main
arguments undermine, the argument from the illusion or deceptiveness of the
senses undermines ordinary sense perception. Undermining ordinary sense
perception and scientific observation as well as the more theoretical parts of
the physical sciences and hence these sciences as a whole is the dream
hypothesis, while the deceiver God hypothesis undermines the pure mathematical
sciences such as arithmetic and geometry. Descartes' metaphysical doubt
emphasizes purging the old falsehoods and buildings up again from the bedrock of
the indubitable of our existence as thinkers. Whether or not the extensiveness
of such skepticism used by Descartes is necessary, remains open for doubt. But
for one to gain any knowledge what so ever, they must be capable of doubting at
some point or another, rather than accepting all that they may hear. It would be
extremely credulous and naive to never doubt or question it is only natural to
doubt and challenge that which one does not believe, and to a certain extent,
being the natural extent, it is useful and necessary, "When Descartes
begins to doubt in an epistemological mode, he cannot stop short of doubting
whether Cartesian Doubt 9 he himself exists as a doubter" (Prado 1992)..

Perhaps, when the poet Charles Bukowski said "the more crap you believe,
the better off you are," he realized that such an extensive doubt can be
harmful to the majority of people, because they are in fact "better
off" believing in their senses, their God, and their ability to determine
whether they are sleeping or awake. It is possible that it may be beneficial to
live and die being deceived, and be ignorant to that deception, than to live and
die searching for truth where truth may not be found, for the true determinant
to whether such an extensive skepticism is beneficial or necessary depends on
the individual. Neither Descartes nor Bukowski can speak for anyone other than
themselves.