René Descartes is perhaps one of the most important philosophers to emerge out of the Renaissance. At an age when most people are just graduating, he was beginning to challenge all previous assumptions about our knowledge of the world, starting with the premise `Cogito, ergo sum`, otherwise known as `I think, therefore I am`. From this point on, scepticism would be built into inquiry, method would supersede practice and the mind would transcend the body.
Rene Descartes was born in 1596, near Tours in France. He was to be educated at a Jesuit college, which was rooted in scholastic tradition. Apparently, due to fragile health, he enjoyed privileges normally reserved for boys of noble birth. Within this environment, Descartes was to study a broad range of subjects and clearly benefited greatly from a Jesuit education. While Descartes was to remain a devout Catholic throughout his life, he was able to separate reason and faith. By this means, he retained the ability to be sceptical of both philosophical and theological positions taken by the Church, while apparently maintaining his Catholic beliefs .
On a sceptical note, in the spirit of Descartes himself, even at the height of the Renaissance, few people were prepared to dissociate themselves from the norms of the community in which they lived and depended. Today, the United States is the most technically advanced nation on Earth. It is claimed that 90% of its scientists are either agnostic or atheists. However, in contrast, not one of its elected members of Congress will admit to being an atheist. Is this probability, prudence or just political necessity?
Initially, Descartes took a degree in law, but by 1619, he is studying mathematics and the science of natural phenomena. Around this time, he also begins work on `Rules for the Direction of the Mind`, which is to be his first major philosophical treatise on the proper method for pursuing either science or rational theology. Over the next decade, Descartes is to alternate between his study of mathematics and science. By 1629, Descartes has moved to Holland, where he is to live in seclusion for some 20 years. These years produce three major works, the first on optics, the second on meteorology and geometry, which were both published in 1637. The third entitled 'The World' was only published after his death. Unfortunately, only fragments of Descartes' early writings survive. However, after Descartes moved to Amsterdam, he began working on the philosophical ideas for which he is best remembered. His work `Discourse on the Method` was also published in 1637. However, by 1640, he had expanded his ideas in this original work regarding metaphysical issues and, in 1641, published a follow-up work called `Meditations on First Philosophy`. In 1649, Descartes moved to Stockholm to become a philosophy tutor to the court of Queen Christina of Sweden. Unfortunately, Descartes was to die shortly after in 1650.
Although Descartes was to become hugely influential in the centuries following his death, his philosophical and scientific work never had the `official` recognition he had hoped. Initially, much of his work received condemnation, usually on religious grounds, and by 1633, the Church in Rome had banned his work. Then, by the early 18th Century, it was to suffer from the rise of empiricalism in both Britain and France, and the near universal acceptance of the Newtonian worldview.
Based on Descartes' earliest education with the Jesuits, it had been stressed that the method of acquiring knowledge was as, if not more, important than the knowledge itself. This is contrary to the tradition of most education in which the rote memorizing of classical and scientific material was, and to some extent, still is the norm. This approach in his formative years was to underpin much of Descartes' later work on scepticism. While over the course of his career, he was to write on optics, the soul, the human body and mathematics, he is probably best remembered for his philosophical questioning, e.g.
How do we know things to be true?
How do we distinguish the false from the true?
Much of Descartes' fame and influence is based his initial work entitled `Discourse on Method`, published in 1637, but subsequently consolidated in his work entitled `Meditations on First Philosophy`, published in 1641. Although the following breakdown of this work was not used by Descartes, it hopefully helps provides an initial overview of how his ideas evolve throughout this work:
- Part-1: Scepticism
- Part-2: Method
- Part-3: Problems
- Part-4: Certainty
In the first part, Descartes tries to describe the need for radical scepticism. In part, it is also an important consideration of our own central discussion about how we, as individuals and as a collective society, have come to view the universe. In many cases, people simply accept what other people tell them, but we will also reflect on the question that was raised in Descartes' mind:
If the entire universe were a lie, created by the devil, how could you prove that what you see around you is not a lie?
Descartes found that when he investigated the human sciences, he could not prove them true in the face of other objections that they were false. As a consequence, he concludes that he had to quite literally stop believing in everything. Therefore, in Part-2, he starts by refusing to accept anything that might be false. He reaches the conclusion that he needs to first tear down, before he can rebuild a more solid structure or methodology on which to base his thinking. In Part-3, he go on to describes the problems this entails. For example:
If you stop believing in everything, including mathematics, how do you live your life?
At this point, he tries to establish some preliminary rules. For example, if you are not sure that anything is true, you need to make some provisional assumptions, based on what other people believe, especially moral beliefs. Once you establish truth, you can begin to reject what other people believe to be true. However, Part-4 starts by highlighting Descartes' increasing desperation to find some initial truth upon which to build a foundation for his methodology. Descartes comes to realise his starting point must be `Cogito, ergo sum` or `I think, therefore I am`. Descartes' reasoning being that if he did not exist, he would not be able to think. It is from this point, which Descartes goes on to prove subsequent truths, such as the existence of God .
Descartes, like Aquinas, only rationalized the existence of God based on philosophical arguments. From the perspective of a proven empirical truth, such arguments may always remain subjective. However, Descartes argues that the foundation of any truth can only be based on subjective experience.
What is so important about the `cogito` is that it forwards the idea that the individual subjective experience is the foundation of truth. This single, radical notion would go on to transform thinking in Europe. Descartes' philosophical method was also intended to be a method for science. His concern with scepticism, in all its forms, was therefore directed, not only at religious scepticism, but everything in general. Given Descartes declared belief in God, his position on this matter has been characterized as follows:
- The world created by God was intended by Him to be known, if
and only if human beings go about the activity of knowing properly.
- How the activity of knowing might be properly conducted is the issue of methodology.
Descartes believed that existing methodologies of the day were limited. For example, he believed syllogistic logic, as used by Aristotle, could only communicate what was already known, while geometry and algebra were either too abstract for practical application or too restricted in shapes considered aesthetically correct. The essence of Descartes' methodology is summarized as follows:
- Never accept anything as true without evidence of its truth.
- Divide each difficulty into parts to assist in its resolution.
- Increase in knowledge from the simple to the complex.
- Check and review all truths.
An alternative interpretation of Descartes' method is that it is based on three mental operations:
These three abilities constitute human reasoning. Intuition involves directly assimilating the simplest components of a subject. Deduction is not merely syllogistic, but a process which infers the required relationship between objects. Enumeration is a process of review required when deductions become too complex that we risk error. However, although Descartes' method had its advocates, he also had his critics. Leibniz apparently described Descartes' rules as amounting to:
- Take what you need,
- Do what you should,
- And you will get what you want.
Despite his religious beliefs apparently being deeply rooted in Catholicism, Descartes also reflected a new mood to analyze what we believe to be true. While Descartes himself would not really use his own methodology of scepticism to fundamentally change the worldview around him, he did plant the seeds of the idea.