Rene Descartes (1596 – 1650) French philosopher and mathematician. Descartes is considered the founder of modern philosophy for successfully challenging many of the accepted wisdom of the medieval scholastic traditions of Aristotelian philosophy. Descartes promoted the importance of using human reason to deduct truth. This principle of reason was an important aspect of the Enlightenment and the development of modern thought. His work in mathematics was important for the later work of Isaac Newton.
Early Life Rene Descartes
Rene Descartes was born in La Haye en Touraine, France on 31 March 1596. His family were Roman Catholics, though they lived in a Protestant Huguenots area of Poitou. His mother died when he was one year old and he was brought up by his grandmother and great uncle.
The young Descartes studied at a Jesuit College in La Flèche, where he received a modern education, including maths, physics and the recent works of Galileo. After college, he studied at the University of Poitiers to gain a degree in law.
In 1616, he travelled to Paris in order to practise as a lawyer – according to the wishes of his father. But, Descartes was restless in practising law, he travelled frequently seeking to gain a variety of experiences. In 1618, he joined the Dutch States Army in Breda, where he concentrated on the study of military engineering, which included more study of mathematics.
Visions of a new philosophy
In November 1619, whilst Descartes was stationed in Neuburg an der Donau, he stated that he received heavenly visions, whilst he was shut in his room. He felt a divine spirit had infused his mind with the vision of a new philosophy and also the idea of combining mathematics and philosophy.
Descartes had always sought to be independently minded – never relying on books he read; this vision increased his independence of thought and is a characteristic aspect of his philosophy and mathematical work.
In 1620, Descartes left the army and visited several countries before returning to France. He was now motivated to write his own philosophical treatises. His first work was Regulae ad directionem ingenii (1928) Rules for the Direction of the Mind. It set out some of Descartes principles for philosophy and the sciences. In particular, it expressed the importance of relying on reason and the use of mental faculties to methodically work out the truth.
Rule III states:
“As regards any subject we propose to investigate, we must inquire not what other people have thought, or what we ourselves conjecture, but what we can clearly and manifestly perceive by intuition or deduce with certainty.”
– Rene Descartes
Descartes moved frequently in his early years, but he came to settle in the Netherlands, and it was here that he did most of his writings. As well as philosophy, Descartes continued his mathematical studies. He enrolled in Leiden University and studied mathematics and astronomy.
Discourse on the Method
In 1637, Descartes published some of his most important works, including Discours de la méthode. This stated, with Descartes’ characteristic clarity, the importance of methodically never accepting anything as true – which had not been properly examined.
Although Descartes remained a committed Catholic throughout his life, his writings were still controversial for the time period. In 1633, Galileo’s works were put on the prohibited list, and his own Cartesian philosophy was condemned at the University of Utrecht. In 1663, shortly after his death, his works were placed on the Index of Prohibited Works by the Pope.
Ironically, Descartes claimed his meditations were aimed to defend the Catholic faith – through the use of reason and not just relying on faith. However in retrospective, many believe Descartes’ willingness to start with doubt, marked an important shift in philosophy and religious faith. No longer was Descartes stating that the authority of the church and scripture should be assumed – Descartes shifted the proof of truth onto human reason; this was a very influential aspect of the Enlightenment and marked an erosion of authority by the Church.
Descartes willingness to doubt the existence of God led many contemporaries to doubt his real faith. Some believed Descartes may have been a secret Deist, who gave the impression of being a committed Catholic for practical reasons. A biographer of Descartes, Gaukroger states that Descartes remained a committed Catholic throughout his life – but, he had a complementary desire to discover the truth through reason.
Descartes wrote on a variety of subjects, relating to philosophy. In 1649, he published 1649 Les Passions de l’âme (Passions of the Soul) a work which sprung from a long correspondence with Princess Elisabeth of Bohemia concerning issues of morality and psychology. This work led to Descartes being invited to the Royal Court of Sweden by Queen Christina.
In 1650, Descartes reluctantly travelled to Sweden and gave the Queen several philosophy lessons early in the morning. However, it was not a success; there was a lack of understanding between the two. More seriously, in the cold castle, Descartes contracted a form of pneumonia and he died shortly later on 11 February 1650.
He had a relationship with a servant girl Helena Jans van der Strom. With Helena, he fathered a child and was distraught when she died in 1640.
Descartes pioneered a new approach to modern philosophy, which was different to the preceding Aristotelian approach. Descartes took great pride in stating that his conclusions were reached from his own deduction and not relying on the works of others.
Descartes methodology of philosophy involved beginning with a metaphysical doubt about everything and from this basis of ‘being unsure of anything’ – seeing what he could prove to be true.
Cogito ergo Sum (“I think therefore I am”)
From this basis of doubt, Descartes started by deducting that the first thing he could be sure of was his own thoughts. If he was doubting, then there must be someone doing the doubting. It is this that led to his famous dictum Cogito ergo Sum (“I think therefore I am”). Descartes believed that it was only his capacity to think and deduction that was reliable – he believed relying on the senses were open to doubt.
From this premise, Descartes was able to offer an ontological proof of a benevolent God Descartes believed that the idea of God’s existence was immediately inferable from a “clear and distinct” idea of a supremely perfect being.
An aspect of Descartes philosophy was the distinction of the mind (or soul) and body. Descartes wrote how the mind could control the body and vice versa.
From Descartes’ philosophy, he later developed a form of moral philosophy which were effective for functioning in the real world. This involved obeying laws and customs of the country in which he lived, avoiding extremes and adopting practices which were judicious to those around you. His third principle expresses the importance he attached to controlling the mind and desires.
“Endeavor always to conquer myself rather than fortune, and change my desires rather than the order of the world, and in general, accustom myself to the persuasion that, except our own thoughts, there is nothing absolutely in our power; so that when we have done our best in things external to us, our ill-success cannot possibly be failure on our part.”
Rene Descartes, Discourse on the Method, Chapter III
Descartes developed Cartesian or analytic geometry, which uses algebra to describe geometry. His work on algebra was influential in the later work of Isaac Newton (on calculus and cubic equations) and Gottfried Leibniz (infinitesimal calculus).
Descartes was also a polymath, who also investigated a wide range of fields, including optics, astronomy and music.
Major works of Descartes include
1618. Musicae Compendium. – a work on the aesthetics of music
1626–1628. Regulae ad directionem ingenii (Rules for the Direction of the Mind).
1637. Discours de la méthode (Discourse on the Method).
1637. La Géométrie (Geometry).
1641. Meditationes de Prima Philosophia (Meditations on First Philosophy),
1644. Principia Philosophiae (Principles of Philosophy)
1649. Les passions de l’âme (Passions of the Soul). Dedicated to Princess Elisabeth of the Palatinate.
Rene Descartes – Meditations and Other Metaphysical Writings
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Rene Descartes – Biography
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