“The first modern philosopher” – that’s probably the most common caption of René Descartes. He revolutionized scientific methodology and set it on new grounds; established a new conception of human nature; put forward novel proofs of God’s existence while at the same time reviving the so-called problem of evil; linked algebra to geometry; performed avant-garde experiments on animal physiology. Is it enough?
A French Gentleman in Holland
Descartes was born in 1596 in La Haye en Touraine, a small town in the Indre-et-Loire, now named after him – Descartes. His father was a local politician and his mother died when he was only one year old. Descartes was educated at the Jesuit College at La Flèche and then at the University of Poitiers, where he graduated in law in 1616. In 1618 he moved to Holland, to attend the International College of War. His main works were written while maintaining quarters in most of the cities of the Ducth Republic, between the 1630s and ‘40s. He died in the winter of 1650 in Stockholm, Sweden, where he had recently moved to tutor the Queen Christina of Sweden. Some say he died of pneumonia, others from a poisonous communion wafer.
Not Your Typical Prof
As several others key figures in Early Modern Philosophy, Descartes was not an academic. In 1623, he sold some family assets investing the revenues in bonds; these provided a yearly allowance sufficient to devote his time to study and research only. Such circumstances explain also one of his most proverbial habits: he used to work in bed throughout the morning, till noon.
Descartes was a prolific writer. Besides numerous letters, his chief philosophical production includes four books. The Discourse on the Method (1637), dedicated to the foundations of scientific knowledge. The Meditations on First Philosophy (1641), probably his major work, an agile text devoted to provide a new foundation for philosophical thinking. The Principles of Philosophy (1644), a longer volume deepening and reconsidering many of the issues faced in the Meditations. The Passions of the Soul (1649), a fascinating inquiry into the relations between free will, passions and morals, stemming primarily from his philosophical exchanges with Elizabeth of Bohemia, one of the key figures in Early Modern Philosophy. The four publications made it into the Index of Prohibited Books under pope Alexander VII, in 1663.
A New Foundation for Science and Philosophy
The first and chief goal of Descartes’s Discourse, Meditations and Principia is to offer a new foundation to scientific and philosophical discourse. The main obstacle was skepticism. Revived most starkly by Michel de Montaigne’s Essays (1580), skepticism points at the unreliability of the sources of knowledge. Consider, for example, weather forecasts. Do you really know that it’s going to snow tomorrow? Forecasts proved wrong many times over in the past – how can you ensure me that they won’t be wrong in this case? The strategy adopted by Descartes was to first raise the most radical skeptical doubts, and then dispel them.
The Right Look
In the First Meditation, the reader is presented with three skeptical doubts. The first regards knowledge that comes from the senses. Take eyesight. If you watch a straw entering a glass of water, the straw will look bent to you, even though you know that it is not. When observed from the terminal of JFK airport, the Empire State Building looks small; once you are under it, it looks gigantic: what is the correct size? Can you really trust your eyesight when it comes to judge – say – the shape or size of things? How about their colors?
Is Life a Dream?
The second doubt concerns the very existence of material objects, a metaphysical doubt. Are you really awake at this time, reading an article by your About guide Andrea Borghini, or are you sound asleep? Don’t dreams look as veridical as the experience you are going through presently? How can you rule out that your whole life is but a dream?
What if God Was an Evil Deceiver?
Still, one could reply, even if the reliability of the senses and the existence of material objects can be doubted, two plus two will equal four. Well, here comes the third doubt. What if you were but the creation of an omnipotent evil deceiver, who ‘engineered’ you so to systematically get your math wrong (besides what you learn through the senses and what you regard as existent)? This is the famous evil deceiver hypothesis, also known as the hyperbolic doubt, raised by Descartes to once and far all prove the revival of skepticism wrong.
“Doubtless, then, I exist, since I am deceived; and, let him deceive me as he may, he can never bring it about that I am nothing, so long as I shall be conscious that I am something.” In the Second Meditation Descartes finds the key out of the skeptic’s trap. I have to exist, since I am thinking. (The phrase “I think, therefore I am” is found in the Discourse.) On this intuition, evident “by natural light” – as Descartes would have put it – rests much of modern philosophy. Self-consciousness is the most distinctive human trait.
So, I exist. Cool. What’s next? Can I use this as a trampoline to prove the existence of something besides me? Descartes makes a very audacious move here: from my thinking I can prove nothing less than God’s existence. How? Well, go through your ideas. Some certainly were derived from things you experience from the senses: pineapple taste, for example. Some ideas can be fancied by mixing and matching your experiences; for example, unicorns or the creatures in the TV series Visitors. But the idea of God could not have been produced by anything less perfect than God. Where else could you have derived it?
No More Doubts!
Yet, if God exists, then the three skeptical doubts can be dispelled. The third one is patently wrong, since God’s perfection is incompatible with the hypothesis of God deceiving us. Deception is a shortcut for imperfect beings. Therefore, I can trust my mathematics, if I have sufficient evidence for my results, because God provided me with a proper instrument for this purpose: reason. And I can trust that I am not dreaming – washing away the second doubt – if I have sufficient evidence to think that I am not. Finally, I can trust my senses, if properly testing the information they carry over.
The errors proceeding from the senses, however, prompted Descartes to lay down a ‘bomb’, which opened the way to modern theology and ethics. So, if God is infinitely good and omnipotent, how come there are some innocent people dying because of the errors deriving from their senses? Think for example to those afflicted by dropsy. If God is omnipotent, couldn’t God have bestowed upon us senses that were not prone to such an illness? If God is infinitely good, how come God tolerates an illness that kills innocents? The justification of God’s omnipotence and infinite benevolence in light of the existence of evil goes under the name of theodicy. Theodicy is a key chapter of modern theology, and Descartes can be considered as its modern founder. The century following the publication of the Meditations saw a heated debate around this issue, with authors such as Bayle, Leibniz, Voltaire, and Hume.
Descartes is famous also for having formulated the thesis of mind-body dualism. It should be relatively simple, at this point, to state it. Consider again the Cogito. This principle is attained while we are supposing to know nothing, not even that we have a body. Thus, we know of our own existence independently of our knowledge of our own body. Now, for Descartes, what we perceive clearly and distinctly to be different, is indeed different. The mind is non-extended and it is always active, that is thinking, processing information. The body, instead, is extended and passive: it moves only if an external force is exercised upon it, as the laws of classical mechanics sketched by Galileo prescribed. Thus, mind and body are completely heterogeneous. Humans are the union of these two substances. Yet, how do mind and body communicate? Through the pineal gland, suggested Descartes. The question still awaits proper reply.
And It Keeps Going …
In his writings, Descartes offers also first-rate considerations on a wide range of other topics. These include: free-will; bodily sensations and their mental counterparts (e.g. goose bumps and the mental feeling of cold); the relationship between sensations and moral sentiments; custom and morality.
In the Discourse we read: “It is not enough to have a good mind. The main thing is to use it well.” Descartes lived up to his words, it seems.