Transcript The Rationalist - Cengage Learning

Archetypes of Wisdom
Douglas J. Soccio
Chapter 9
The Rationalist: Rene Descartes
Learning Objectives
On completion of this chapter, you should be able to
answer the following questions:
What is rationalism?
What is the coherence theory of truth?
What is the “methodic doubt”?
What are innate ideas?
What are a priori ideas? What is a posteriori knowledge?
What is skepticism? What is cogito?
What is the “evil genius”?
What is materialism? What is Cartesian dualism?
What is the ontological argument?
What is the mind-body argument?
The Problem of Authority
The origins of modern philosophy lie in:
The proliferation of scientific advances.
The loss of central authority by the Roman Catholic
church.
The decline of a stable social order as a result of that
loss of authority.
The mind of René Descartes.
René Descartes
René Descartes (1596-1650) was born into an old and
respected family in the French province of Touraine.
After completing his studies as the Jesuit college at La
Flèche, he earned degrees in law at the University of
Poitiers.
On November 10, 1619, he had a revelation in which he
“discovered the foundations of a wonderful new science.”
He believed he had been divinely encouraged to establish a
universal method of reasoning, based on mathematical
principles, which would guarantee the absolutely certain
truth of its results.
The Solitary Intellect
Solitary and secretive, Descartes preferred to avoid the
distractions and commotion of city life and social
involvements.
He lived alone most of his life, and during a twenty-year
period lived in twenty different houses.
Living this way, he was able to study philosophy,
geometry, physics, optics, circulation, and other topics.
In September 1649, he became a tutor for the Queen of
Sweden.
But the weather and his lifestyle got the best of him, and he
died of pneumonia on February 11, 1650 at age fifty-three.
Rationalism
Rationalism is an epistemological position in which
reason is said to be the primary source of all knowledge,
superior to the senses.
In general, rationalists believe that abstract reasoning can
produce undeniable, absolutely certain truths about nature,
existence, and the whole of reality.
These truths are called a priori, or innate, ideas – because
they are discovered independently of experience, without
empirical observation or experimentation.
Descartes stands not only as the “father of modern
philosophy,” but as the original archetype of the modern
rationalist.
Against Disordered Thinking
Of great importance to Descartes was understanding an
accurate method for how to think about philosophy.
Descartes cautions that “in a too absorbed study” of the
works of earlier thinkers, we become “infected with their
errors, guard against them as we may.”
Therefore, Descartes feels that philosophical inquiry
requires a method in order to avoid errors.
Discourse on Method
Descartes develops the Discourse on Method, in which he
spells out rules aimed at attaining certain knowledge.
For example, “One we have chosen a subject to study, we
should confine ourselves to what we can clearly intuit and
deduce with certainty for ourselves.”
For when we accept views solely on the weight of the
authority or prestige of those who hold them, we become
non-rational at best.
We should order our thinking and, instead of becoming
memorizers, become thinkers ourselves.
The Method of Doubt
Descartes proposed to use the new spirit of scientific
inquiry and mathematical rigor to reexamine…everything!
Anything that did not rest solely on “the clear light of
natural reason,” was suspect.
In his effort to provide an absolutely certain foundation for
philosophy, he discovered methodic doubt – that is,
doubting until something is found which cannot be
doubted.
Whatever remained would be absolutely certain.
Standard of Truth
Descartes proposed that only those things we can accept as
“clear and distinct” should be accepted as true.
“Clear” he defined as “that which is present and apparent
to an attentive mind.”
“Distinct” he defined as “that which is so precise and
different from all other objects that it contains within itself
nothing but what is clear.”
What he has in mind are examples from geometry and
mathematics, which he felt should serve as the standard of
truth.
Innate Ideas
A priori knowledge: knowledge that is known “prior” to or
independently of sense experience.
A posteriori knowledge: knowledge that is known “after”
or dependent upon sense experience.
To Descartes, we can know some things are a priori
because they are innate (that is, they have been implanted
in our minds by God).
Descartes gives as an example the idea of a triangle.
The Cartesian Genesis
The method of doubting Descartes proposes is spelled out
in his Meditations, which he begins by asking himself what
he can be skeptical about.
The begins by mentioning all the things he has learned
through his senses – in effect, everything around him.
He then considers the thought that perhaps he is just
dreaming, even though things seem real enough to him
(after all, dreams can sometimes seem that way).
Then he pushes his doubt even further, by wondering how
he could ever tell whether the world really is as he
perceives it, or if God is actually an “evil genius” who is
deceiving him.
The Doubting Self
After calling everything he perceives into doubt, Descartes
wonders whether he can call his own existence into doubt
as well. But he finds that this is impossible.
For in order for him to doubt himself, he must go through
the process of doubting (which, for Descartes, is a process
of thinking).
This means he’s found something certain: himself as a
thinking thing (or a mind).
The famous Latin sentence, “Cogito, ergo sum,” literally
means “I think, therefore I am.”
In other words – I can’t doubt my existence, since I have to
be the thing doubting if doubting is being done.
The Cogito
This is good news for Descartes: discovering at least one
thing that cannot be doubted provides him with the
beginnings of a sure foundation.
For the cogito is a thinking thing, a mind, with all of the
innate ideas that make a mind a mind, which make a mind
like Descartes’ – or yours – capable of rational thought.
And one of the innate ideas that Descartes has is of God,
an infinitely perfect being.
The Innate Idea of God
At this point, there are two things whose existence
Descartes is assured of: himself as a thinking thing and his
innate idea of God.
But even if he cannot doubt the existence of his own mind,
he knows he is not responsible for its existence.
He also knows he is not responsible for the existence of his
innate idea of an infinitely perfect being, since he is a
finite, imperfect being.
That suggests that the source of both Descartes’ mind and
its innate idea of an infinitely perfect being is God. That
is, that God actually exists.
Descartes’ Ontological
Argument
Descartes turns back to the Middle Ages for his argument
concerning God’s existence. The idea is essentially: the
idea Descartes has is of a perfect being, but unless that
being actually exists, it is not perfect (i.e., perfection
entails existence).
This is an ontological argument, an attempt to prove the
existence of God by referring either to the meaning of the
word God or to the purportedly unique quality of the
concept of God. In other words, the argument may be
“true by definition.”
The purest form of the ontological argument first occurs in
the writings of St. Anselm (1033-1109).
Reconstructing the World
Once Descartes is assured of the his own existence and that
of God’s, everything else falls into place.
The world is roughly as he perceives it, since God cannot
be an evil genius and be the infinitely perfect being
Descartes has in mind.
Also, the mind and the body are two distinct things, since
that is the way Descartes perceives them as being, and he
now knows he is not being deceived about such things.
He is a mind thinking about the physical objects he
perceives all around him, and can now be certain that
science is getting the world roughly right (only roughly,
since our senses are finite). Errors are due to our will to
know running ahead of our good, but imperfect, abilities.
Cartesian Dualism
This leaves us with a problem, though: if the mind and
body are different in kind, how do they communicate?
How do you get ideas (from extended non-thinking
things), and how do you (a non-extended thinking thing)
tell your body to act on them once you have them?
This is the result of Descartes’ philosophical dualism – the
position that existence is divided into two completely
distinct kinds of things.
The Mind-Body Problem
Descartes was a devout Catholic, and well aware of the
challenge to religion posed by the reemergence of
materialism in modern science.
Other philosophers, notably Thomas Hobbes (15881679), were arguing that everything is composed of matter
and can be explained by physical laws.
This is a form of monism – the belief that everything
consists of only one, ultimate, unique substance, in this
case, matter.
For a monist like Hobbes, thinking is merely a complex
form of behavior, and the body a fleshy machine. The socalled “mind” can be reduced to the functioning of the
brain.
From Cosmos to Machine
According to the feminist philosopher Susan Bordo,
“Cartesian Modernity is inherently linked to the repression
of nature and women.”
For Bordo, the problem is that objectivity, rather than
meaning, became the chief philosophical issue.
The masculinization of science thus leads to an alienation
from nature, the repression of women and a de-emphasis
on the family.
Discussion Questions
Descartes says that “it were far better never to think of
investigating the truth at all, than to do so without a
method.” Why was he so troubled by disorganized thinking
and blind curiosity?
What do you think he might say to us about basing our
opinions regarding global warming, creationism versus
evolution, and other controversial issues on what we
“learn” from movies, TV, the Internet, politicians, and
professors?
What methods do you use to choose among competing
“experts” and positions?
Chapter Review:
Key Concepts and Thinkers
Rationalism
Innate ideas
Coherence theory of truth
Methodic Doubt
A priori knowledge
A posteriori knowledge
Cogito, ergo sum
Ontological Argument
Materialism
Behaviorism
Mechanism
Reductionism
Dualism
Monism
Pluralism
al-Ghazali (1058-1111)
Susan Bordo (b.1947)
Rene Descartes 1596-1650)
Thomas Hobbes (15881679)
St. Anselm (1033-1109)