René Descartes on Science, Philosophy, and God

There are some people who, for whatever reason, seem to have been either iconically or erroneously labeled in popular perception, and that judgement clouds all future thoughts of the person. Occasionally it’s an invention, experiment, or song (or other cultural reference) that we automatically associate with the person’s name. If I mention the name Pavlov, what comes to mind? Bells and drooling dogs, most likely. If I say Edison, does a light bulb go off in your head? Sometimes it’s judging a person’s life (for good or ill) by one particular act, quote, or moment in history. If you were to hear someone mention “Watergate,” you’d almost certainly think of Richard Nixon, and the fall of the Berlin Wall would probably make you think of Ronald Reagan (or maybe David Hasselhoff).

Placing Descartes Before Discourse?

Perhaps in a similar way, one of history’s most ill-labeled figures is René Descartes. Often thought of as a skeptic rationalist by Christians, largely because he’s frequently touted as a dyed-in-the-wool humanist natural philosopher by the neo-atheist crowd. But is this really based on fact, or revisionist history?

René was born on March 31, 1596, in La Haye, France (the town is now named Descartes, in his honor).

In Danny Faulkner’s recent article on Richard Proctor, he mentioned a forthcoming Descartes article. What better day to run an article on Descartes than on what would have been his birthday? Yes, René was born on March 31, 1596, in La Haye, France (the town is now named Descartes, in his honor). Little is known of his early life, except that his mother died when he was just a little over a year old, and that his father served in the Parliament of Brittany and was almost never home. Young René stayed with his grandmother and then his great uncle in his early years.

René Descartes—Education & Military Career

In 1607, at the age of 11, Descartes entered the newly founded Jesuit College of La Flèche, where he graduated around 1614. His studies included Latin and Greek grammar, classical poets, philosophy (mostly Aristotelian) consisting of logic, morals, physics, and metaphysics. He also learned physics and mathematics in the final three years of study, including some works of Galileo. By the age of 18 Descartes had (for the time) a very well-rounded education. Not satisfied with just this, René, after graduation in 1614, studied for two years (1615–16) at the University of Poitiers, earning degrees in canon and civil law in 1616.

In 1618 René entered military service for several years. During this time period, most armies hired “mercenaries” to add to their existing force, and it was not uncommon for young men to join up for ideological or even strictly financial reasons.

Chance Meetings and Vivid Dreams

They immediately struck up a friendship, with Beeckman becoming a surrogate mentor to Descartes, influencing and urging him in mathematical studies.

While in Breda serving with the army of Maximilian I, Duke of Bavaria in 1618, Descartes met Isaac Beeckman, a Dutch mathematician and natural philosopher (today we would call people such as Beeckman a scientist). They immediately struck up a friendship, with Beeckman becoming a surrogate mentor to Descartes, influencing and urging him in mathematical studies. It was during this time that Descartes made several key discoveries or advancements in mathematics, most notably adding algebraic coordinates and formulae to geometry. Although it was close to another 200 years before his system was widely developed, it was named Cartesian geometry in his honor.

While in the town of Ulm (in southern Germany) on the night of November 10, 1619, Descartes had a series of three dreams which all pointed him to establishing a new method for scientific inquiry and unification of the sciences. Looking back on Descartes life, it is fairly evident that he dedicated his life to fulfilling that goal.

During the 1620s Descartes devoted most of his time to mathematics and science. As early as 1626 Descartes had formulated his laws on optics, although they did not see print until 1637. Descartes is usually credited as being the co-discoverer of the laws of refraction along with Snell, although Snell’s unpublished work goes back to 1621.

Cogito Ergo Sum

It was the 1637 publication of The Discourse on Method that became one of Descartes’ most famous works. It included the Discourse and three scientific essays. Optics and Meteorology were purely scientific and Geometry was mathematical. The Discourse was what would today be called philosophical, but at that time, philosophy was considered a science, and the content of the Discourse was meant to be a methodology for seeking truth in science.

It is in the Discourse (written in French) that we first see the phrase “Je pense, donc je suis” ("I think, therefore I am")—the most famous quote from Descartes. He would later write this phrase in Latin “Cogito ergo sum” in his 1644 work Principles of Philosophy that brought the phrase into mainstream scientific (and later public) circles.

As Dr. Faulkner mentioned in his Proctor article, this is often portrayed as a defiant remark of mankind asserting himself above everything (including, in some circles, God) due to his intellect. But Descartes would likely have been appalled at this interpretation of his words. His starting point was that he had been given an intellect by God. Descartes then argued that the very fact of having a thinking mind pointed to an infinite mind which could only be God’s.1 In his “Second Meditation,” from his 1641 work Meditations on First Philosophy, written in Latin, he expounded on his earlier French work The Discourse on Method, and it was here that he first formulated his later Cogito ergo sum. It then follows in his “Third Meditation” that we learn more of Descartes’ views of God.

Descartes constructs an argument for the existence of God that starts from the fact that he has an idea of an infinite being.

Descartes constructs an argument for the existence of God that starts from the fact that he has an idea of an infinite being. The argument is intricate and, to the modern reader, perhaps a bit confusing. It invokes the metaphysical principle that “there must be at least as much reality in the efficient and total cause as in the effect of that cause.”2 Descartes then applies that principle not to the mere existence of the idea of God as a state of mind, but to the content of that idea. Descartes characterizes that content as infinite, and he then argues that a content that represents infinity requires an infinite being as its cause. He concludes, therefore, that an infinite being, or God, must exist. Descartes then argued that, if we think of the existence of a concrete physical world around us, as we all do, then an omnipotent, omniscient, and omnibenevolent God would ensure that such a world does in fact exist for us.3 He then equates in his “Fourth Meditation” an infinite being with a perfect being and asks whether a perfect being could be a deceiver. He concludes: “It is clear enough from this that he cannot be a deceiver, since it is manifest by the natural light that all fraud and deception depend on some defect.”4

In his “Fifth Meditation,” Descartes reasons that the first and primary substance is God, whose essence is perfection. In fact, God is the only true substance, that is, the only being that is capable of existing on its own. The other two substances, mind and matter, are created by God and can only exist through his ongoing act of preservation or conservation, called God's “concurrence.” It can be clearly seen from these discourses that Descartes was no atheist, and indeed tried to show through reason a basic ontological argument for God.5

René Descartes—Trading Science for Philosophy?

As mentioned above, philosophy was regarded as a science at this time, so there is no clear point at which we could claim Descartes went from “scientist” to “philosopher.” But by the 1640s it is clear that he wrote more on the philosophy of science than he did on empirical scientific or mathematical topics. But we must remember that Descartes was seeking to implement a methodology for “doing better science” with his philosophical arguments. The most likely reason Descartes is less remembered for his scientific contributions is that after his death he was labelled as “the father of modern philosophy.”

The science of Descartes’ day was heavily influenced by accepting Aristotelian ideas uncritically. Descartes deplored this inclination and fought against it. His clear intent was to show that God-given reason should be used in solving problems and seeking out truth, and that feelings-based philosophies should be scrutinized and questioned.6

Skeptic, Rationalist, and Dualist

What causes many Christians to make Descartes out to be such a villain is his usage terms like rationalization, dualism, reductionism, metaphysics, natural philosophy, instinctual/mechanical philosophy, skepticism, and self-awareness.

What causes many Christians to make Descartes out to be such a villain is his usage (and in many cases they were either inventions of or complete revolutions of) terms like rationalization, dualism, reductionism, metaphysics, natural philosophy, instinctual/mechanical philosophy, skepticism and self-awareness. In fact, at first blush, most Christians thinking of the above terms in how they are used today would likely label Descartes as antagonistic to God and Christianity. But as one of René’s contemporaries would have said “therein lies the rub.” The terms that Descartes either invented or brought to the public’s eye did not mean the same then as they do now, and in fact most of them are based (at least loosely) on biblical or Christian principles.

Descartes was a skeptic—of blindly accepting things that were not critically evaluated. He was a reductionist, in that he wanted to strip away all preconceived notions and take an idea or mechanical object apart and reformulate it. He was a dualist in that he believed that the mind and body were separate entities, and he also distinguished the consciousness from the brain. He was a rationalist who reasoned that an infinite God had given mankind an intellect, which in turn should be self-evident to humanity that there was an infinite God.7 He was a metaphysicist who believed in an absolutely certain and secure epistemological foundation for all that is or would be discovered.8 Far from being anti-God, it can be easily shown that these principles are mentioned in Scripture and fit within a biblical worldview (Deuteronomy 11:18; Job 38:36; Psalms 147:5; Proverbs 18:15, 25:2; Ecclesiastes 1:13; Romans 1:19–20; 1 Corinthians 6:20; 1 Thessalonians 5:23; 2 Timothy 1:7; Hebrews 4:12).

While Descartes could not be described as an evangelical Christian, he can also not be lumped into the atheistic camp either.

While Descartes could not be described as an evangelical Christian, he can also not be lumped into the atheistic camp either. Ultimately, whether he was a Christian or not is between him and God, and we just cannot know. But it should be noted that, although Descartes’ believed in God and thought that human reasoning should (and did to him) point to an all-wise, benevolent and creator God, it was his reliance on human reasoning which later rationalists used to dismiss God.

Descartes’ reasoning had established a physical world which was of a mathematical character and permitted math and physics to be used to explain it. And although God was integral and indispensable to Descartes' method of arriving at a physical world, “once such a world was accepted, it was no longer necessary to involve God in the description and measurement and explanation of how things work. Thus, the process of science was freed from theological constraints and interference.”9

The Final Irony in René Descartes’ Life

As mentioned earlier, Descartes remained a Roman Catholic throughout his life. But as the Galileo affair occurred during his lifetime, he found that his philosophical rebellion against Aristotelian “science” was not viewed favorably by the Catholic church. In fact the Catholic church viewed him as a dangerous influence, putting his works on the Index of prohibited books (Index librorum prohibitorum) in 1663 (although some sources say 1667). In addition to his antagonism to Aristotelian influence on the sciences, his last published work, Passions of the Soul (1649) made the Catholic Church worried that his account of matter might be inconsistent with the Eucharist, and that he did not make the mind sufficiently independent of the body.10

After initial resistance from Protestant circles, many of his writings became popular, and even embraced.

But after initial resistance from Protestant circles, many of his writings became popular, and even embraced. Some protestant philosophers like Kant, Berkeley, and Reid openly borrowed and then furthered Descartes’ rational arguments for the existence of God. (However, they like Descartes also opened the door for rationalistic atheism). And it is telling that his most productive writing period in the 1630s occurred when he was in protestant Holland, with little fear of censorship as would have been the case in France.

Towards the end of his life (October 1649), Descartes accepted a position as philosophy tutor to Queen Christina of Sweden. During his four months in Sweden, he wrote the statutes for the Swedish Academy of Arts and Sciences, and on February 1 he delivered them to Queen Christina. That same day he caught pneumonia and died ten days later on February 11, 1650.11 The philosopher and scientist died writing science and teaching philosophy.