Study Questions for Descartes’s Discourse, Part IV

and Meditations, I




  1. What three specific arguments for skepticism does D list?  Does D really doubt everything?  Again, is it even possible to achieve a state of universal doubt?
  2. Why does he reject every proposition that depends on sense perception?  On chains of reasoning (as in mathematics)?  Why does he pretend that none of his thoughts or perceptions are no less illusory than his dreams?
  3. What is the first certainty Descartes found after his process of “methodological doubt?”
  4. How does D get to the famous cogito ergo sum, "I think therefore I am"?  What follows from this first principle (according to D, anyway)?
  5. Why does D identify himself with his mind rather than his body -- and why separate mind and body in the first place?  How does he arrive at the view that mind and body are totally distinct things, that almost any property of one is absent from the other?
  6. Descartes next turns to the question of what makes a proposition true and certain.  What makes him think that the Cogito proposition ["I am thinking, therefore I exist"]  is true and certain?  What does he decide to take as the criterion of truth?  When he adopts this criterion as a general rule, what problem does he mention that it has?
  7. What is the larger meaning or significance of reason and self-evidence?  What sort of breakthrough does D think he has achieved?
  8. Why is D so sure that God exists?
  9. What makes Descartes think that he is not a perfect being?  Why does he take the source (ultimate cause) of his ability to conceive of something more perfect than himself to be itself more perfect than he is?  Does he think that such external things as the earth, the stars, heat, and light exist independently of him?  Why not?  Can he himself be the source or cause of his idea of a being more perfect than himself?  Why not?  Why does he think that the source or cause of this idea must be another being more perfect than himself?
  10. Explain Descartes's strategy for coming to know the nature of God.  What attributes does he attribute to God?  What attributes does he think God cannot exhibit?
  11. How does Descartes conceive of the object studied by geometers?  Why are geometrical demonstrations (geometrical proofs) widely believed to possess great certainty?  Do these demonstrations assure us of the existence of their objects?  E.g., do triangles exist in the real world (i.e., in rerum natura)?
  12. Does the idea of a triangle contain or include the equality of its interior angles to two right angles?  Does it contain existence?  Does the idea of God contain existence?  What does Descartes think follows from these observations?  How certain, then, is the existence of God?
  13. What kind of certainty do we have about such apparent facts as that we have bodies, that the earth and sun exist?  Are any facts as certain as the existence of God and of our soul?  How does Descartes appeal to dreaming to cast doubt on the existence of an external world?
  14. What is the difference between moral assurance and metaphysical certainty?





  1. Why did it take so long for Descartes to start to establish anything firm and lasting in the sciences.
  2. At the beginning of Meditation I, Descartes says that “he will apply [himself] earnestly and unreservedly to this general demolition of [his] opinions. (Descartes, 59) Why on earth would anybody want to do that? (See both the Synopsis, pp. 54-56, and Meditation I for the answer.)
  3. In the normal course of life, is it desirable to believe only what is certain, or is it acceptable to believe claims that are less than certain? Why? Is Descartes advocating that we only believe what is certain?
  4. What strategy does Descartes say he is going to use, in performing this task? To demolish all these opinions, does he think he needs to show they are all false, or something weaker than that? Does he think he needs to take up each belief individually, or is there a way to process hoards of them at a time?
  5. Why does he start his doubting process with opinion gained from or through these senses? How can he doubt them?
  6. The second doubt that Descartes brings forward begins with the fact that he sometimes dreams. What beliefs does he think are called into doubt by this argument? Which of his beliefs does he suggest are left untouched by the Dream Argument, and why does he conjecture that the Dream argument leaves them unscathed? What name does he give to the things these beliefs are about? Which disciplines investigate these things?
  7. Why does Descartes need the Dream Argument to show that he cannot trust the deliverances of his senses if he already has established that his senses sometimes deceive him?
  8. The third doubt that Descartes brings forward begins with his belief in God. What additional beliefs does Descartes mean to call into doubt by this argument, and how? What objection does he consider, and how does he reply to it?
  9. The fourth doubt that Descartes brings forward starts with the possibility that God does not exist. What further beliefs does Descartes mean to call into doubt by this argument, and how? If God does not exist what would be the source of our own existence?
  10. For what reason does Descartes pretend that all his opinions are false? What does this reveal about the difference between claims that are certain and claims that are reasonable to believe?
  11. Why does Descartes compare himself to a prisoner at the end of the First Meditation?


Read also the first three paragraphs of the Second Meditation.





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