René Descartes is generally considered the
father of modern philosophy. He was the first major figure in the
philosophical movement known as rationalism, a method of understanding
the world based on the use of reason as the means to attain knowledge.
Along with empiricism, which stresses the use of sense perception
rather than pure reason, rationalism was one of the main intellectual
currents of the Enlightenment, a cultural movement spanning the
seventeenth and eighteenth centuries that revolutionized the Western
world. In tandem with men like John Locke, John Hobbes, and Voltaire,
Descartes spurred society to re-examine its traditions and institutions,
leading to massive social upheaval. Both the American and French
Revolutions were based on Enlightenment theories, and the ways we
approach science, math, philosophy, and the idea of the self were
radically transformed during the period.
Descartes was born in 1596 in La
Haye, a small village near Tours, France. The son of an aristocratic
family, Descartes was enrolled at age six in the Jesuit College
at La Flèche in Anjou. Because Descartes had always been somewhat
sickly, his teachers allowed him to stay in bed until noon every
day. Descartes attributed his most important ideas to this habit,
and said he did his best thinking when he spent the morning in bed.
Despite the religious underpinnings of the school, it was open to
the free study of humanities and science. Descartes immersed himself
in a wide range of subjects, excelling especially in mathematics.
At La Flèche, Descartes’ professors favored the Aristotelian method
of study, which held that nature was inherently stable and ordered
and that one could rely on information derived from sense perceptions
to deduce truths. Descartes would later question this fundamental
tenet of his education. The college also taught mathematics separately
from the study of physical world, which was founded on philosophy,
rather than what we now consider scientific method. Descartes had
doubts about this divide, and one of the major results of his later
work was the use of mathematics in the study of physics.
After leaving La Flèche, Descartes enrolled in the University
of Poitiers, and he obtained a law degree in 1616. Despite his ill
health, he then enlisted in the military. His military service,
along with his family’s modest wealth, gave Descartes the opportunity
to travel. He happily settled in one foreign locale after another
for most of his life. While in Holland in 1618,
Descartes composed a brief treatise on music, titled Compendium
Musicae, not published until after his death. The next
year, Descartes traveled in Germany, where, in a stove-heated room
on November 10, 1619,
he had a vision of a new system of mathematics and science. He would
later tell the story of this revelation in Discourse on
the Method.
In 1628, Descartes began to compose Rules
for the Direction of the Mind, a short treatise outlining
a new method of thought. By using a set of rational principles,
Descartes had been able to eliminate many of his own doubts about
fundamental ideas. Although the book was originally intended to
be composed of three sections of twelve rules, Descartes only completed
the first twelve. These first twelve deal with simple propositions.
The incomplete second set covers a method for dealing with “perfectly
understood problems”—that is, problems that can be expressed through
simple mathematical equations. The third section was intended to
deal with “imperfectly understood problems,” problems too complex
to be reduced to an equation. Descartes hoped to show that even
these problems could be expressed through mathematics.
In 1633, the Inquisition issued
a formal condemnation of the work of the Italian scientist Galileo.
He argued, contrary to the traditional notion that Earth was the
center of the universe, that Earth revolves around the sun. Galileo
was condemned to death for heresy, but his sentence was later reduced
to house arrest. At the time, Descartes was working on The
World, a study he thought would revolutionize the study
of physics. After Galileo’s house arrest, Descartes voluntarily
suppressed The World, fearing the wrath of the Catholic
Church.
It wasn’t until 1636, when Descartes
was forty, that he published his first work, Discourse on
the Method, a discussion of how he had made use of the
rules he’d begun to lay out in Rules for the Direction of
the Mind. Discourse on the Method relates
the series of revelations Descartes had in 1619 while in the stove-heated
room in Germany. After confessing how he came to doubt all his knowledge, Descartes
shows how he used his rules to solve profound problems. He resolves
the problem of personal existence in one of the most famous philosophical
statements of all time, Cogito ergo sum, or “I think,
therefore I exist.” He also offers rational proofs that the human
mind is separate from the body, that the mind outlives the body,
and that God exists. The Discourse was meant to
serve as an introduction to three essays Descartes had been laboring
over—Optics, Meteorology, and Geometry—which
contain science now regarded obsolete. The Discourse,
however, remains one of the world’s most influential works of philosophy.
The work that cemented Descartes’ fame was Meditations
on First Philosophy (1641). Here
Descartes addresses the concerns and attempted refutations various
readers sent to him after reading the Discourse.
The theories in Meditations would change the way
people thought about their minds and bodies and the relationship between
the two, but Meditations also contains arguments
that later became known as the “Cartesian Circle” because of the
apparent circularity of their logic. Meditations was
followed by Principles of Philosophy (1644),
which attempts to reduce the universe to its mathematical foundation.
By the time Principles was widely read in Europe,
Descartes was the toast of continental intellectual circles and
was awarded a pension by the king of France.
But as his fame grew, so did the demands on his time.
In 1649 Descartes moved from Holland to Stockholm, Sweden, at the request
of Sweden’s nineteen-year-old Queen Christina, and agreed to work
as her philosophy tutor. Ignoring Descartes’ poor health and his
preference for staying in bed until noon, Queen Christina scheduled
her lessons with him for 5:00 a.m. Lack of sleep and inhospitable
living conditions took their toll on Descartes, and, in 1650, he
died of pneumonia at age fifty-four. Despite his attempts to stay
on the church’s good side, Descartes’ books were placed on the Index
of Prohibited Books after his death, so for years no Catholic was
allowed to read them.
