Lecture 9/23 – Background to Descartes

I. Introduction: Descartes’ Life and Works A. Descartes (1596-1650) 1. Born in La Haye, France in 1596. 2. 1606 – 1614 Descartes studies at the Jesuit University of La Fleche where his philosophical education would have focused on Aquinas and Aristotle – the dominant world view at the time. 3. 1616 – Received his law license. 4. 1637 – Discourse on Method 5. 1641 – Meditations on First Philosophy 6. 1644 – Principles of Philosophy 7. 1649 – Descartes moves to Sweden and tutors Queen Christina. 8. 1650 – Dies in Sweden in 1650. B. Descartes revolutionizes philosophy in two main ways. 1. In terms of epistemology, Descartes explores important issues via the first person point of view. He asks, “What can I from my own subjective point of view know about myself and the world around me.” This approach dominates philosophy after Descartes. 2. Descartes will also transform the way in which we think about substance. C. Descartes is a pivotal figure in the history of ideas since he writes at a time when the world is changing in important ways. The Meditations is a much discussed work. 1. Renaissance (1350-1550) 2. Reformation (Beginning in the First Half of the Sixteenth Century) 3. Scientific Revolution (Beginning in the Second Half of the Sixteenth Century) D. At the same time however, Descartes does not represent a total or complete break with the old world view. Though scientific, Descartes is deeply Christian and shares many assumptions and concerns with Medieval philosophers. E. Since Descartes opposes many of the old ideas and yet at the same shares many other ideas of philosophy before him, we need to examine some main themes of medieval philosophy in order to fully understand his thought and place in the history of ideas.

II. Themes of Medieval Philosophy A. Substance: 1. The two main thinkers in medieval philosophy are Augustine (354-430) and Thomas Aquinas (1225-1274). The former is influenced by Platonism and the latter by Aristotle via Islamic commentators. 2. In general, medieval philosophers attempt to bring together the ancient theories of either Plato or Aristotle with Judaic, Islamic, or Christian theological doctrine. They attempt to systematically reconcile reason and faith. 3. After the Council of Trent (1542), Catholic leaders responded to the Protestant Reformation by reaffirming traditional catholic teaching, which was basically grounded in the thought of Aquinas. This meant that the dominant world view in Europe at least, was Aristotelian. 4. One subject which interested the Medieval philosophers was substance and their conception of substance was essential based on Aristotle. a. Aristotle’s conception of substance = hylomorphism = all substance is a combination of two things: matter and form. The former is potentiality and the latter actuality because Aristotle thought that strictly speaking, matter without form was nothing. Consider the following: i. A bronze sculpture of Athena is comprised of two things: the bronze, which by itself is only potentially a sculpture of Athena and a form which in this case is equivalent to a shape which is imposed on the bronze by a sculptor. ii. An oak tree is composed of two things: some matter – wood, etc. and a form which in this case is not simply shape although the oak tree may have a similar shape to other oak trees. In this case, form is the rational principle of the tree’s organization, which coordinates different parts of an oak tree and integrates the functions performed by those respective parts in the just the right way. b. Aristotle identified Four Causes in nature: (See Physics Handout) i. Material – corresponding to the matter of substance discussed above. ii. Formal – corresponding to the form of substance discussed above. iii. Efficient – cause of motion or change. Aristotle writes in the Physics that the father is an efficient cause of the child because he causes he/she to come to be. iv. Final – this is the end or purpose of something in nature, i.e. it is what a thing is for. Thus the final cause of a house is to provide shelter. Living things in nature also have final causes for Aristotle. The final cause of a tiger cub is to grow up and be a full grown tiger. c. Descartes in his theory of substance and causation will essentially do away with the second and fourth of the above state causes. We do not need to know anything about forms and final causes to engage in meaningful scientific investigation from the modern point of view. B. God: Proving the existence of God as necessary. 1. This concern by Medieval philosophers is I think an instance of a broader theme implicit in Augustine (See Confessions Handout) – using reason to understand certain theological beliefs to the best of our ability 2. There are two main types of proof for the existence of God and Descartes will give versions of both kinds in the Meditations. a. Ontological: Ontology is the study of the essence of being in general, so the ontological proof will try to prove the necessary existence of God by demonstrating that it is part of the essence of God’s being that He or She exist out of necessity. That is to say, one of the defining features which makes God the thing that He is, is that He necessarily exists. b. Cosmological: Cosmology is the study of the universe and more specifically, it is the study of the origin of the universe. In this way, a cosmological proof will try to prove the existence of God by showing that the existence of God is a necessary condition for the possibility of the universe or some feature of the universe actually existing. This way of proving the existence of God I believe is made famous by Aquinas who gave five ways to prove the existence of God (See the Summa Handout). One proceeds as follows: Things move in our world. If some thing moves, there most be some X which causes the thing to be moved. But since this X must itself be in motion to cause the thing to moved, either we trace the cause of motion to an infinite number of events in which case the original motion is not explained or we posit the existence of some first cause of motion which is itself unmoved. This unmoved mover must exist necessarily in order to explain the motion, which is a feature of our universe, and of course this necessary unmoved first mover is identified with God. C. The Theory of Illumination: 1. The theory of illumination is a theory intended to explain how we know certain intellectual truths such as 2 + 2 = 4 and truths of logic such as something cannot be both X and not-X at the same time and in the same way. The theory derives from interpretations of an analogy which Socrates presents in Book VI of the Republic. The theory argues that just as the sun provides light and visibility enabling us to perceive with our sense objects in our visual field, so there is some source of intellectual illumination which enables us to know the above stated intellectual truths in our minds. 2. Socrates had labeled the source of this intellectual illumination the “Good.” 3. Plotinus (205-270) in his work on the Enneads labeled the source of this illumination the “One.” 4. Augustine probably never read Plato but is influenced by Platonism via Plotinus’ interpretation. In any event, Augustine identifies the source of intellectual illumination as God. In this way, for Augustine it is only when we have divine illumination that we are able to grasp these intellectual truths. 5. This theory of illumination gets critiqued and discussed throughout the Middle Ages and after thinkers such as Aquinas and John Dun Scotus, the source of illumination is no longer viewed as external to our mind. God has made our minds work in such a way that whenever a mind focuses attention on certain intellectual truths, this illumination takes place and allows us to “see” with our mind the truths in question. 6. Descartes often uses a “natural light” metaphor in order to explain how it is that certain basic, self-verifying, intellectual truths are known to any rational mind when attention is given to those truths. This metaphor relies heavily on this long tradition of the theory of illumination going back to Plato. And I think it will be easier to understand a criterion Descartes uses – the criterion of clear and distinct ideas – if we are aware of this theory and its history.