Rene Descartes: Reasoning of What is Real Without Doubt by yRKfBim


									Rene Descartes: Reasoning of What is Real Without Doubt
Rene Descartes rejected the use of our senses as a means of understanding reality. Like Plato,
Descartes turned to the mind and to rational thought to discover truth.

Descartes began his deliberations by doubting the existence of everything that could be
doubted and by accepting only those truths he knew with complete and intuitive certainty.
When Descartes was absolutely, rock-solid certain about something, and could not deny it any
way, he accepted that idea as truth or building block from which he could deduce other

Using this process, Descartes decided that almost everything in existence could be doubted.
Soon, however, Descartes realized that the process of doubting required a mind that was, in
fact, doubting. He concluded that he, Descartes, or at least his mind, must exist in order to
doubt. His famous phrase "I think, therefore I am" (cogito, ergo sum), became for Descartes a
solid foundation upon which he could determine other truths.

What Descartes meant is that any attempt to doubt one's existence as a thinking being is
impossible because to doubt it to think and exist. Try for a moment to doubt your own
existence, and you'll see what Descartes meant. The self that doubts its own existence must
surely exist in order to be able to doubt in the first place.

Descartes also considered the existence of God, a being he defined as perfect in all ways.
Descartes asked himself: How could he, Descartes, as an imperfect being, have developed any
idea at all of perfection? Descartes concluded that the idea of perfection could only have been
communicated to him from a perfect being, a being he called God. Descartes' reasoning led
him to two conclusions of which he was sure, without a doubt: the existence of his own mind,
and the existence of God.

Descartes' Ideas About Material Objects
Is there any doubt of the world of reality, of material objects? Is it possible,      A system of logic,
asked Descartes, to doubt the existence of apparent reality? Using deduction          inference and
and insight, Descartes noted that we experience and believe in the existence of a     conclusion drawn
material and real world. Descartes had already deduced the existence of a             from examination
perfect being, God. A perfect God, he concluded, would not deceive or allow           of facts.
humans to believe falsely in the existence of material reality. Therefore,            drawn from the
Descartes concluded, the world of material objects must exist.                        general down to
                                                                                      the specific
Next, Descartes turned his attention to the investigation of the nature of material
reality. The investigative process used was deductive reasoning. Descartes reasoned that the
material world is different from the mind, which is a thinking substance, and different from God,
a perfect being. Although material objects may not be exactly as we experience them- in colour
or texture, for example- he reasoned that they do contain some characteristics of which we can
be certain. Material objects occupy space; they possess shape, size, position, and movement.
These aspects of the physical world affect our sensory organs, causing us to experience light,
colour, smell, taste, sound, heat and cold.

Descartes used this line of reasoning, coupled with certain intuitive insights and deduction, to
determine, to his satisfaction, the existence of three major substances: mind, God, and material

One problem Descartes left others to deal with was the distinction between mind and matter as
different substances. Descartes himself was firmly convinced that the mind was of different
quality than material objects. This point of view has troubled many philosophers to this day.
The issue has become known as the mind-body problem, and it raises a number of questions.
If mind and body are different substances, how do they communicate? How can the material
world have an impact on the mind? How can the mind influence the material world? We all
understand that there exists some connection between mind and matter, but what is it? When
we decide to pick up an object from the floor, we succeed in communicating to our body that it
must do so. Events that happen in the external world often affect the way we think on different
levels. Descartes attempted to deal with this conundrum by suggesting that the human pineal
gland at the base of the brain is the switching station that facilitates communication between the
mind and matter. Scientific research, however, has proved his theory incorrect.

Adapted from Philosophy: The Power of Ideas and Philosophy in Action

  1. State the problems of reality that Descartes was trying to solve and his answers.
  2. Map or web out Descartes' thought process. What conclusions does he draw and in
     what order?
  3. Define the mind-body problem.
  4. For hundreds of years, the world's greatest thinkers have puzzled over this argument
     and tried to pick holes in it. Consider the following criticisms:

Criticism 1: Circular Argument
A circular argument has the form: A proves B and B proves A; therefore, nothing has been proved. For
example: The bible can be trusted because God says its true; you can trust God because the bible says
God only tells truth.

Think about the statement "I think, therefore I am". Can you see why some argue it is circular logic? How
might Descartes defend the Cogito against this criticism.

Criticism 2: Hume's Objection
David Hume, in his Treatise of Human Nature, argued that when we focus in on our own thoughts, we
can’t be aware of anything else except the thoughts themselves. We can’t actually simultaneously be
aware of a self that has the thoughts. Therefore, Hume argues that Descartes can only derive from the
statement “I think”, that “Therefore, there is thinking going on. In other words, for Hume, Descartes is
going too far by positing a self.

This has proved a very popular line of objection to Descartes through the centuries. What do you make of
this objection? What might Descartes have replied to Hume?

Criticism 3: Find anything funny here?
Descartes’ Cogito has proved a source of humour over the centuries. For example, here is a joke that
has done the rounds of the internet:

     Rene Descartes walks into a restaurant and sits down for dinner. The waiter comes over and asks if
     he'd like an appetizer.
     "No, thank you," says Descartes, "I'd just like to order dinner."
     "Would you like to hear our daily specials?" asks the waiter.
     "No!" says Descartes, getting impatient.
     "Would you like a drink before dinner?" the waiter asks.
     Descartes is insulted, since he's a tee-totaller (One who abstains completely from alcoholic
     "I think not!" he says indignantly, and POOF! he disappeared.

And another:

     How many Cartesians does it take to change a light bulb?
     None--unfortunately, when the bulb blew out, they were all so shocked that they stopped thinking for
     that brief moment--and 'poof', they all just blinked out of existence.

    Within the humour lies a possible line of criticism. Can you articulate it? What might Descartes reply?
    How effective do you find this criticism?

To top