Hallo, this is Dr. Bin Song at Washington College.

As explained in the previous unit of Modern Philosophy, underlying the enterprise of modern philosophy termed by Descartes as the “Tree of Philosophy” is the root of “metaphysics” which addresses the most generic traits of basic substances of the world, viz., soul, body and God. Therefore, to appreciate the title of Rene Descartes as “Father of Modern Philosophy,” we will spend the following two weeks to read the entirety of Descartes’s “Meditations on First Philosophy,” and I hope you can get as much insight as you can from this incredibly rich, and quintessentially “modern” text of philosophy.

Being among the enshrined modern philosophical classics, none of a single word in these Meditations can be overlooked by contemporary readers. However, these Meditations were after all written almost 400 years ago, which would naturally indicate some unfamiliar nature to readers today. One of the difficult reasons to read Descartes’s Meditations is to grasp how Descartes used old, scholastic terms and jargons to express his modern thought. If we gradually peel away these pre-modern layers from the kernel of his thought, we will find the distinctively modern traits of Descartes’s thought in the kernel, and thus, feel immediately connected to it. In the following, I will provide a brief and preliminary explanation of prominent themes of Meditation I-III, and I hope it can facilitate your actual reading of the book.

Firstly, the title of the book “Meditations” is fairly interesting. Starting from Aristotle’s “contemplative life,” running through Marcus Aurelius’s “Meditations” and Augustine’s “Confessions,” the philosophical tradition of the West evolved into Descartes’s “Meditations” to have indicated a rich “meditative” lineage where “meditation” is understood as a systematic reflection upon philosophical problems, and the reflection is aided by a certain kind of focused mental discipline. This richly meditative tradition of the West tends to be overlooked by contemporary readers since the current use of the term “meditation” is easier to be connected to Hindu, Buddhist or other non-Western practices of meditation. However, if we read the entirety of Descartes’s Meditations, we can still find some similarity between this meditation of a philosopher’s with other more religiously oriented ones. To put it briefly, this philosophical meditation also needs a two-way system of descending and ascending, or one of reduction and recovery. In Buddhist Chan meditation, for instance, you need to focus upon your breathing so as to reduce your consciousness to a peaceful and all-encompassing base, and then, employ that purified consciousness to re-contemplate worldly phenomena so as to live a mindful life here and now. Similarly, Descartes uses the method of “doubt” to challenge the validity of every piece of knowledge he acquired before; once he got to the bottom of his doubt, he found one piece of knowledge that he cannot doubt, viz., the existence of the thinking “I”; and then, he would do further contemplation upon all ideas that exist within this thinking “I” so as to check whether any of these ideas can provide certain knowledge of the outside world. I believe every reader, as long as they closely followed each word of Descartes’ Meditations, would also experience such an intense process of purification and reunification of human mind, which makes Descartes’ thought process deeply “practical” and “performative” in the regular sense of doing “meditation.”

Secondly, the method of “doubt” used by Descartes to get to the all-encompassing base consciousness of “I think,” is not a normal one. It is termed as the “hyperbolic doubt” which would consider any piece of human knowledge as completely false as long as it indicates a scintilla of uncertainty and dubitability. Using this hyperbolic doubt in Meditation I, Descartes threw away all pieces of knowledge, which he acquired through sense, imagination, memory and even pure intellect, with only the sheer activity of “I think” remaining as the rock bottom of human consciousness that cannot be thrown away any more. Here, the radical departure of Descartes’s philosophy from the pre-Modern Aristotelian one cannot be more visible: as we explained before, Aristotle’s natural philosophy is based upon the common-sensical observations of worldly phenomena. However, here, Descartes says that humans’ “common-sense” does not make any sense until every piece of it gets radically doubted and thoroughly scrutinized. Since doubting and scrutinizing require the ability of independent and free human thinking more than anything else, we can surely discern a distinctively “modern” sign of Descartes’s philosophy, just as we once characterized Copernicus’s heliocentric astronomy as indicating the same strength of human thinking and thus, as the starting point of modern scientific revolution.

Thirdly, since Descartes does not take “common-sensical” observation as the starting point of the pursuit of human knowledge, the more authentic approach to obtain human knowledge for Descartes is termed as “idealism,” which is distinguished from another very important, later lineage of modern thought, viz., “empiricism.” Descartes’s idealism suggests that in order to obtain human knowledge about anything in the world, we cannot start from a naïve perception of the world which takes the existence of things in it as granted, since the very existence of things in the world has been put into radical doubt in Meditation I. Rather, because the inner world of human subjectivity, which is termed by Descartes as “I think” or pure thinking, is more certain than anything else, we need to search for “ideas” that exist in our mind first, and then, infer whether these “ideas” correspond to realities outside the human mind; in other words, we need to examine whether these “ideas” can inform us of any knowledge about the outside world. Through this idealistic approach of epistemology, Descartes categorizes the origin of human ideas into three groups: ideas can be innate, invented, or affected from outside. Descartes also scrutinizes these ideas one after another regarding their validity of informing knowledge of objects outside human mind. In other words, rather than taking “realities” to be the prior origin of “ideas,” Descartes pays his primary attention to “ideas” in human mind, and then ask whether “ideas” inform humans of “realities.” Since “ideas” are more primary than “realities,” the role of autonomy and human free thinking gets prioritized and glorified during the process, which is surely a re-affirmation of the “modernity” of Descartes’s thought.

Finally, another significant aspect of Descartes’s Meditations is his theology, viz., his reflection on the existence of God and the role of the idea of God in regaining the validity of human knowledge that he has radically doubted prior to the conclusion of “I think; therefore I am.” For Descartes, it is a crucial step for the aforementioned epistemological approach of idealism to know that God is the creator of “I,” and more importantly, God is so good that He would not make “I” commit mistakes even on ideas which “I” can perceive vividly and clearly. Only after making sure the ultimate kindness of God, viz., “God is not a deceiver” in Descartes’s own words, Descartes thinks that we can believe our “natural tendency” to think of certain ideas in our mind, such as those mathematical ideas and sensory perceptions, as corresponding to realities outside of human mind. Be this as it may, our wondering is that: is God really an absolutely necessary idea to Descartes’s system? Or as some scholars intend to argue, is Descartes’s meandering thinking on God just a sign of Descartes’s “political shrewdness” since he did not want his writings and his person to undergo the same destiny of Galileo Galilei under the censorship of the Church? I would be very interested in hearing your thought on these questions.

In a word, in Meditation I-III, Descartes finds the undoubtable foundation of human knowledge, “I think therefore I am,” via a radical method of hyperbolic doubt, and then, after proving the existence of a kind God, he intends to re-ascend from the all-encompassing base consciousness of “I think,” and regain human knowledge via the approach of idealism. Please do read the Meditations word-by-word, and my summary here by no means captures the full glory of this quintessentially modern writing at the dawn of modern philosophy.

Hallo, This is Dr. Bin Song at Washington College.    

In 1644, Descartes published his Principles of Philosophy, and intended to promote it as a textbook of philosophy to be adopted by universities of Europe at that time. Descartes knew that this was deliberately to challenge the dominant role of Aristotelianism in the European academia. After all, the replacing of one textbook with another means a great deal. Although whether Descartes succeeded to promote his textbook in the institutional level is another story, he is indeed universally acclaimed by later historians as the father of modern philosophy.

Before Descartes, we discussed Aristotle, Copernicus, and Galileo in this second section of “modern scientific revolution” at the course of “Modern Philosophy.” We find that although Copernicus and Galileo laid out a very robust refutation against key points of Aristotle’s natural philosophy, none of these scientists’ thought is comprehensive enough to address the established Aristotelianism as a whole. As we have discussed, the philosophical system of Aristotle was so comprehensive as to be able to include everything that humans could know in his time. Therefore, to challenge the official status of Aristotelianism, Descartes’s philosophy must also be no less comprehensive. Descartes likened his comprehensive version of philosophy to a tree:

“Thus the whole of philosophy is like a tree. The roots are metaphysics, the trunk is physics, and the branches emerging from the trunk are all the other sciences, which may be reduced to three principal ones, namely medicine, mechanics and morals. By ‘morals’ I understand the highest and most perfect moral system, which presupposes a complete knowledge of the other sciences and is the ultimate level of wisdom.” (Principles, 9B:14)

Put in the background of the entire corpus of Descartes’s works, why Descartes thinks of philosophy as such would be more comprehensible. Metaphysics studies the most generic traits of things in the universe which exist under three major categories: soul, body and God. Physics studies the “body” part of the universe, and furnishes the laws of nature which explain the movement of varying bodies in the world. Medicine and Mechanics are two branches of applied physics, which are about how to cure human diseases and how to design technologies to alleviate human labor, two crucial areas pertaining to the convenience and sustainability of mundane human life. The “morals,” or the ethics is about what humans should do in varying situations, and according to Descartes, this is the highest branch of human knowledge since it needs all sorts of other knowledge in order to deliver the right ethical decisions.

Among all these parts of philosophy, we’ll focus upon “metaphysics” in the following weeks, where we’ll scrutinize Descartes’s famous argument for “I think therefore I am” and how he built his metaphysical system addressing the substances of soul, God and body. However, when Descartes presented his tree of philosophy in an intended textbook, his thought was in a relatively mature stage. The tree didn’t include much information about how he got to the root of his philosophy, viz., that dualistic metaphysics of soul and body, in the first hand. In order to understand how he got there and prepare our study of his metaphysics, we therefore need to trace his philosophical career back to a much earlier stage.

Before Descartes turned into his metaphysical thought in 1628, he was a very successful mathematician and physicist. Seen from the perspective of the on-going scientific revolution, the greatest contribution Descartes made as a scientist is surely his invention of analytic geometry, which unifies algebra and geometry, and hence, paves the way for the birth of calculus in Newton’s and Leibniz’s thought.

There are two major points we need to grasp in the ground-breaking work of the Geometry of Descartes.

Firstly, the unification of algebra and geometry leads to the full digitization of the objective natural world, which is unimaginable before Descartes. The crucial step for Descartes to achieve this is to illustrate that all major algebraic operations in Descartes’s time, including addition, subtraction, multiplication, division, and the square root, can correspond to a certain segment of a line, and hence, there is no reason to limit human imagination of a magnitude within three dimensions. Instead, a simple line segment can express a magnitude of any dimension, and once discovering the way how to express geometrical figures using algebraic means, the capacity of measuring and calculating natural movement in reality will be exponentially increased. If any one wonders where the idea of the digitization of the entire world in the movie of “Matrix” originally comes from, let’s ask Descartes.

Secondly, to resolve complex geometrical problems in his time, Descartes indicates an unusually high awareness towards the underlying “method” for the desired solutions. For instance, to resolve a geometrical problem, Descartes would firstly assign a letter to each of the known and unknown magnitudes. Then, he would write down as many equations as he can find to express the varying relationships between these unknown and known magnitudes. In the following, he would try to reduce the complex level of these equations so as to find a way to express the unknown from the known. Finally, once he found the answer of the unknown, Descartes would furthermore deduce complex relationships among magnitudes from the newly discovered simple ones. In the work of the Geometry, we can find many concrete examples about how Descartes described and applied this “method.” And the application of this method is so successful that Descartes furthermore thought he should use it to resolve all questions humans can ask, including those most abstruse and abstract ones in metaphysics.

Therefore, in 1637, Descartes published his “Discourse on the Method,” and generalized his “method” in four points:

“The first was never to accept anything as true if I didn’t have evident knowledge of its truth: that is, carefully to avoid jumping to conclusions and preserving old opinions, and to include in my judgements only what presented itself to my mind so vividly and so clearly that I had no basis of calling it in question. The second was to divide each of the difficulties I examine into as many parts as possible and as might be required in order to resolve them better. The third was to direct my thoughts in an orderly manner, by starting with the simplest and most easily known objects in order to move up gradually to the knowledge of the most complex, and by stipulating some order even among objects that have no natural order of precedence. The last was to make all my enumerations so complete, and my reviews so comprehensive, that I could be sure that I hadn’t overlooked anything.” (pp. 9, Discourse on the Method, trans. Jonathan Bennett 2017.)

The four rules are quite self-explanatory, and they can all be understood against the practice Descartes conducted in his analytical geometry. In other words, in any pursuit of human knowledge, Descartes believes we should aim for evident knowledge, which should be as vivid and clear as the one of math. Then, we would find all available chunks of information relevant to the solution of puzzles, put them into order, and then, reduce the complex ones to the simple ones, and address the simples ones first with a final synthesis to move from the simple to the complex. Since the aforementioned tree of philosophy is just a result of Descartes’s application of his method which ultimately derives from math, we can safely conclude that although metaphysics is seen as a root of the tree, the real soil to grow the entire tree of philosophy of Descartes is actually his mathematics. So, whoever said that nobody unfamiliar with math cannot learn philosophy? I hope you find some historical predecessor to Descartes’s thought here.

So, how would Descartes employ this “method” so as to create the dualistic metaphysics of “mind” vs “body” as the foundation of modern thought? That will be the question we will tackle for our following learning of modern philosophy. In general, Descartes’s thought is rigorous, methodic, systematic and creative, indeed a rare talent of philosophy, the learning of which can almost be guaranteed to bring a transformation of our own thought.