Special Sub-Topic: René Descartes: Life and Works Click Here To Play: René Descartes: Life and Works

René Descartes was a very famous French philosopher. His works are extremely significant in modern philosophy. He was very popular during his time, but exactly when was his time? Which of these answers contains the correct dates of his birth and death?

31 March 1596 - 11 February 1650. Descartes was born in 1596 in La Haye en Touraine (which has since been renamed "Descartes") and died in 1650 in Stockholm at the age of 53. His tomb is in the church of Saint-Germain-des-Prés, which is also host to a number of cafes that are famous for their link the the philosophical movement of existentialism.

One of Descartes' ideas is considered one of the most important in philosophical history. It involved attaining complete certainty and is known as the "cogito". What is the summary of the argument popularly known as to the English speaking world?

I think, therefore I am. Yes, "cogito ergo sum" translates from Latin to "I think, therefore I am". It is an extremely important argument in the history of philosophy and is used to prove that we actually exist. The fact that we are thinking is the only solid proof that we do exist. Descartes used this as a foundation to come to more certainties (ranging from the existence of his body to the existence of God). Nothing comes from nothing is translated from the Latin "ex nihilo nihil fit" which was popularly argued in ancient Greece, primarily by Parmenides. Existence precedes essence is the key concept in Jean-Paul Sartre's theory of existentialism. The highest good (popularly known by its Latin form "summum bonum") is a concept used by many philosophers, most popularly by Immanuel Kant.

Descartes spent the last seven years of his life teaching and engaging in philosophical correspondence with a princess. He even dedicated his "Principia philosophiae" to her. Who was she?

Elisabeth of Bohemia. She was the daughter of Frederick V and Elizabeth Stuart and is known for her philosophical engagements with Descartes. She requested him as a teacher of philosophy and morals and they began the correspondence that was to last until his death seven years later. 1644 was the year he published "Principia philosophiae" or "Principles of Philosophy" and this was dedicated to Elisabeth.

Descartes is well know for contributions to philosophy, but he was also a prominent mathematician. Which of the following systems did he develop?

Rectangular coordinate system. That's right, Descartes developed the coordinate system of an axis (usually a cross shape) and measured points that we can use to identify a point on the plane. Many argue that this system was also discovered independently at the same time by Pierre de Fermat, who did not publish it, which is why it is credited to Descartes and often known as the "Catersian coordinate system".

Descartes was considered an important figure in the philosophical school of Rationalism.

t. Rationalism is an epistemological view that knowledge can be attained through reason. Descartes was most certainly a rationalist, using reason and deduction in many of his arguments, often stating that only reason and deduction can give us knowledge, as all else fails. Descartes is considered one of the first important rationalist philosophers to emerge in the early Enlightenment.

Which of the following is something which has been named after Descartes?

An asteroid. "3587 Descartes" is the name of an asteroid discovered by Lyudmila Zhuravlyova in 1981 and named after René! There is no such thing as a Descartes shoe or a Descartes protractor, though I'm sure he was a frequent user of both of these things.

There is a scientific experiment named after Descartes which is popular in schools as it is a safe, fun way to demonstrate priciples of buoyancy and the ideal gas law. Which of these is the name used to describe the experiment?

Both of these. Sometimes called a Cartesian diver, sometimes called a Cartesian devil, the experiment involves a pipette or eyedropper (which represents the "diver" or "devil") being placed into a large airtight bottle filled with water. The pipette is filled with enough water and air to keep it buoyant enough to float to the top. When the bottle is squeezed at the sides the pipette sinks (or "dives") to the bottle and returns to the top again when the bottle is released!

Descartes and a servant girl named Helene conceived a baby girl who was born in 1635. What was the name of their daughter?

Francine. Francine was born in 1635 and despite the nature of her conception, she was baptised and recorded as a legitimate birth. Descartes often referred to her as a niece. She died in 1640 as a result of scarlet fever. She was just five years old.

Here is a quote from Descartes. I have removed the part, what are the missing words? - "____ is mankind's most equitably divided endowment."

Good sense. This quote comes from his 1637 work "Discours de la méthode" or "Discourse on Method". The full quote is "Good sense is mankind's most equitably divided endowment, for everyone thinks that he is so abundantly provided with it that even those with the most insatiable appetites and most difficult to please in other ways do not usually want more than they have of this" and is used by Descartes to describe how to think correctly in philosophy.

Descartes died in Sweden, but what disease is believed to have been the cause?

Pneumonia. Descartes was requested to teach philosophy to Christina of Sweden as he had done for Elisabeth of Bohemia. She invited him to Sweden to teach her but warned against immediate arrival as it was during a cold winter. Descartes arrived anyway, but soon the cold began to have an effect. This was coupled with the fact that he was used to staying in bed until midday whereas Christina had him awake and teaching her early in the morning (around 5am). The result of all this was pneumonia which killed Descartes in Febuary of 1650. Thus, the life of Descartes had ended, but his work lives on, and I don't imagine it will ever lose its place as some of the most important work in the history of philosophy.