Rene Descartes was born near Tours in 1596. During his life, he was a contemporary of Galileo and Desargues. His father was a councilor of the local parliament, and Descartes spent most of his time at the family estate at La Haye.
Rene was the second of two sons and a daughter. At age 8, he was sent to a Jesuit school for his formal education. He did very well in both the discipline and the education. He was permitted, due to delicate health, to remain in bed until mid-morning, a habit he kept to later in life.
He left school in 1612 to enter the world of fashion. Upon renewing old acquaintances from school, and with them, studied mathematics in 1615 and 1616. He joined the army in 1617 as was customary to one of his standing.
During his time in the army, he devoted his leisure to the study of mathematics. He dated the first ideas of his new philosophy and of his analytical geometry to three dreams he had on the might of November 10, 1619, while campaigning on the Danube.
He resigned his commission in the spring of 1621. He spent the next five years in travel, but continued to strictly pure mathematics. He also spent some time constructing optical instruments.
In 1628, he met Cardinal de Berulle, the founder of the Oratorians. He was impressed with Descartes and urged him to devote his life to the examination of truth. Descartes agreed, and moved to Holland to free himself from distractions. He lived there for the next twenty years.
He spent the years in Holland giving all of his time to the study of philosophy and mathematics. His first four years were spent writing ‘LeMonde” which was an attempt to give a physical theory of the universe. He discovered that publishing it would bring town the wrath of the church and abandoned it. It was published in incomplete form in 1664.
From there he composed a treatise on universal science published in Leyden in 1637 under the title” Discours de la methode pour bein couruire sa raison et cherchers la verite dans les sciences”. It was accompanied by three appendices entitled “La Dioptrique”, “Les Meteores” and “Le Geometrie”. The last represented the invention of analytical geometry.
In 1641, he published “Meditation” in which he explained his views on philosophy. This was followed in 1647 by “Principia Philosophial” devoted in large part to the physical sciences. In particular, he focused on the laws of motion and the theory of vortices.
He received a pension from the French court in 1647 in recognition of his work. He went to Sweden on the invitation of the Queen in 1649, and died of a lung ailment shortly afterward.
Descartes was a small man with a large head and prominent nose. He was quite cold and selfish and into himself. He was focused on science and mathematics and had no use for art and general learning. He never married but fathered an illegitimate daughter who died quite young.
Descartes was the first to describe the physical universe in terms of matter and motion. He was convinced that mathematics and science could be used to describe everything in nature. While much of his theory has been proven to be inaccurate, his work provided the basis for much of what came later.
His theory of vortices focused on the idea that the matter of the universe must be in motion. Virtually all of his assumptions were arbitrary and unsupported by any investigation. His appendix on “Meteors” for example posits an explanation of rainbows, which is wrong and necessarily so, since Descartes was not at all familiar with the notion of refraction indices.
Even his work on optics was not correct. He also did not seem to credit the earlier work on the subject of Snell although much of the thinking clearly evolved from Snell’s work.
At the end, his two most important contributions were the discovery of analytical geometry, known as Cartesian Geometry, and the theory of vortices. Despite its flaws, the theory of vortices marked a new era in astronomy. It was an attempt to explain the phenomena of the whole universe by the same mechanical laws shown by experiment to be true on earth.
