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Descartes\' First Meditation
Descartes believes that knowledge comes from within the mind, a single
indisputable fact to build on that can be gained through individual reflection.
While seeking true knowledge, Descartes writes his Six Meditations. In these
meditations, Descartes tries to develop a strong foundation, which all
knowledge can be built upon. In the First Meditation, Descartes begins
developing this foundation through the method of doubt. He casts doubt upon all
his previous beliefs, including “matters which are not entirely certain and
indubitable [and] those which appear to be manifestly false.” (Descartes, p.75,
par.3) Once Descartes clears away all beliefs that can be called into doubt, he
can then build a strong base for all true knowledge to stand upon. Descartes
attacks all his previous beliefs by going to the root of their origin, the
senses and intellect. He then supposes to say that everything he presumed to be
absolutely true, such as simple arithmetic, was created by an evil demon.
Descartes starts the first argument by attacking the very basis of his beliefs,
human senses. People learn their beliefs through their external and internal
senses. “All that...I have accepted as most true and certain I have learned
either from the senses or through the senses.” (Descartes, p. 75, par. 3) By
means of the five external senses -- sight, sound, touch, taste, smell -- you
learn various ideas about the world around you. Yet, how reliable are these
external senses, these sources of beliefs? Everyone will admit that their
external senses have deceived them on at least one occasion, and according to
Descartes, it is a mark of prudence never to place our complete trust in
anything that has deceived us even once. (Descartes, p.75, par.3) For instance,
imagine that you spot a person from across the street that looks like your
friend. You run all the way down the street and tap the person on the shoulder,
only to find out that this is not your friend but a person who looks somewhat
like her. According to your sense of sight you believed this person to be your
friend, but your sense deceived you. To build a foundation of knowledge upon
beliefs derived from external senses is foolish since those senses are
deceptive.
Perhaps true beliefs come from your internal senses. Internal senses include an
awareness of oneself, such as believing you have a stomach and a heartbeat,
without seeing them. An example of this internal sense is seen when Descartes
says “There is the fact that I am here, seated by the fire, having the paper in
my hands...and how can I deny that these hands and this body is mine.”
(Descartes, p.75, par.4) His internal sense makes him aware of his hands and body.
Though, Descartes must explore all doubts involving this internal sense if he
wants to use it as his foundation for knowledge.
Descartes brings up the possibility that perhaps at this point, right now, he
is dreaming. A person who is dreaming may have difficulty differentiating
between the dream and reality. Descartes says “How often has it happened to me
that in the night I dreamt that I found myself in this particular place, that I
was dressed and seated near the fire, whilst in reality I was lying undressed
in bed!” (Descartes, p.76, par.1) According to this idea, I may believe, even
now, I am dreaming, this not my body, and I am not writing this paper for
philosophy but I am really lying in bed somewhere sleeping. This dream
hypothesis would invalidate the beliefs that are based on internal sense; for
if you are dreaming then what you believe to be your awareness of self is truly
false. You may say that everyday life exhibits a smoothness and understanding,
which dreams do not. Dreams have little rhyme or reason; while life experience
is orderly and controlled. However, this scale of measuring the differences of
coherence between dreams and reality is unreliable. Sometimes dreams are
incoherent and sometimes they appear to be real. Beliefs derived from internal
senses cannot be true due to the possibility that you may be dreaming.
Descartes goes on to say that maybe the only true beliefs come from intellect,
or clear and distinct ideas. Despite the falsity of internal senses based on
dreams, dreams are based on reality. Whether this hand is real or dreamed, it
is my hand, and it exists somewhere. In addition, certain things are true in
any context, such as “simple Arithmetic, Geometry and other sciences of that
kind which only treat of things that are very simple and very general....For
whether I am awake or asleep, two and three together always form five, and the
square can never have more than four sides.” (Descartes, p.76, par.4) The
philosopher, John Locke argues this point by stating that mathematical truths
are learned from experience and are not innate ideas. Locke, an empiricist,
believes that all people begin with a clean slate and knowledge is added by
experience. Descartes argues that simple mathematical ideas are an Apriori form
of knowledge. Two plus three can never equal fifty-three. Simple mathematics is
a clear and distinct idea, it is self-evident and needs no experience. Yet,
Descartes takes another twist on this concept. He proposes that perhaps even
these clear and distinct ideas cannot provide a foundation for knowledge.
Descartes asks what if he is being deceived. What if all he believes to be
true, is being planted by some sort of intelligence force, such as an evil
demon? Perhaps he is being deceived in these fundamental beliefs. “How do I
know I am not deceived every time that I add two and three, or count the sides
of a square?” (Descartes, p.76, par. 4) This thought experiment leads Descartes
to another method in doubt.
Descartes then goes on to assume that there is a God, who is all powerful, and
created this world; yet he asks, “How do I know that He has not brought it to
pass that there is no earth, no heaven, no extended body, no magnitude, no
place, and that nevertheless they seem to me to exist just exactly as I know
see them?” (Descartes, p.76, par.5) Without a guarantee of reality, maybe all
of his previous beliefs are false. Descartes doubts the supreme goodness of a
God that would let him be deceived even occasionally. Moreover, if a perfect
God does not exist then it becomes probable that Descartes himself is
increasingly imperfect and therefore is constantly being misled. “If, however,
it is contrary to His goodness to have made me such that I constantly deceive
myself, it would also appear contrary to His goodness to permit me to be
sometimes deceived, and nevertheless I cannot doubt that he does permit this.”
(Descartes, p.76, par.5) Descartes assumes the scenario that God is really an
“evil demon“.
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. I shall think the sky, the
air, the earth, colours, shapes, sounds and all external things are merely the
delusions of dreams, which he has devised to ensnare my judgment. (Blackburn,
19) (Descartes, p.77, par.3)
Descartes explores the ultimate source of all his beliefs by bringing up the
evil demon. Now that Descartes has obliterated all the foundations of his
previous beliefs, he can develop a starting point or origin, which all other
true knowledge can be built upon.
Here is a science fiction possibility, which clarifies the evil demon thought
experiment. Imagine that a human being has been subjected to an operation by an
evil scientist. The person’s brain has been removed from the body and placed in
a vat of nutrients, which keeps the brain alive. The nerve endings have been
connected to a super scientific computer, which causes the person whose brain
it is to have the illusion that everything is perfectly normal. The computer is
so clever that, for example, if the person tries to raise his hand, the
feedback from the computer will cause the person to ’see’ and ’feel’ the hand
being raised. The evil scientist can input any information into the computer
and cause the person to experience anything he wishes. This scenario explains
Descartes’ idea of the evil demon. That there is something, which controls all
the thoughts, beliefs, and experiences a person, may have. Descartes continues
with this possibility in order to find a strong foundation for knowledge. As
Descartes says, “I shall remain obstinately attached to this idea...and with
firm purpose avoid giving credence to any false thing, or being imposed upon by
this arch deceiver...but the task is a laborious one.” (Descartes, p.77, par.3)
And so ends the First Meditation.
One philosopher, Hume, argues against Descartes’ conclusions. Hume, like
Descartes accepts the belief that knowledge needs a foundation. Yet, Hume
argues that knowledge cannot have the type of foundation, which Descartes
wanted. Hume argues that the legitimacy of our senses and reasonings is part of
the foundation. All humans, including philosophers, grew up trusting their
senses. For example, people became adept at recognizing danger and trust in
these instincts. This is called natural foundationalism. Unlike Descartes, Hume
believes in trusting your senses. While trying to find a foundation for his
knowledge in the sciences and methodological purposes, Descartes insists on
using his strict method of doubt. Rather than using natural foundationalism’s
basis of knowledge through sense experience Descartes develops his foundation
through reason. Descartes’ hyperbolic doubt is unrealistic.
Hume knows Descartes argument is doomed to failure. As Hume says,
“There is a species of skepticism, antecedent to all study and philosophy,
which is much inculcated by Descartes...as a sovereign preservative against
error and precipitate judgment....It recommends a universal doubt...of our very
faculties...therefore, were it ever possible to be attained by any human
creature (as it plainly is not) it would be entirely incurable; and no
reasoning could ever bring us to a state of assurance and conviction upon any
subject.” (Blackburn, 40)
Descartes idea of ‘all or nothing’ is unnecessary. According to Hume, the evil
demon notion does not matter when it comes to thoughts. The harmony between our
minds and the world is due to the fact that the world influences our minds. The
senses, which we utilize in this world, aid us in the correct way. If they were
untrue we would be unable to survive. Hume does not believe in the need for the
evil demon hypothesis. He believes you can find a foundation of knowledge
through the senses.
Furthermore, there is another response that rids of Descartes’ necessity of an
absolute foundation and Hume’s naturalism. This approach emphasizes the notion
of coherent structures; in which a system of beliefs “hangs together” rather
than having one strict base. This can be portrayed with a ship or web, which
are made up from a tissue of interconnecting parts, and derive their strength
from those interconnections. Each part supports the other part without needing
one base, or foundation to support it. If a belief should be challenged than
all the other parts can support it. As compared to a spider web, if one strand
in the spider web is broken the rest of the web will still remain strong. Any
element can be changed or replaced due to the strength of the connections
between all the elements. However, this approach may backfire if all the
elements have strong connections, and they are all wrong. The argument will
stand strong, but incorrectly. In that case, Descartes’ evil demon hypothesis
seems necessary.
One final problem with Descartes’ evil demon hypothesis is that it causes
Descartes to contradict himself. How can Descartes know the Evil Demon is not
implanting him with the thoughts for his argument in the first place? Since the
evil demon may be deceiving Descartes even about logic and mathematics, perhaps
he is being deceived about his own argument. For instance, might Descartes be
deceived into thinking that the conclusion of the argument “I cannot be certain
about any of my beliefs” follows logically from the premises of the first
meditation. How could Descartes argue for scepticism at all since the evil
demon may be deceiving him about the validity of his arguments? Even if
Descartes were arguing validly, he could never know it.