In Meditations on the First Philosophy, René Descartes delves into epistemology, or the theory of knowledge. He asks questions such as whether there is such a thing as knowledge, and if so, what distinguishes it from opinion. However, in order to answer these questions and to validate knowledge, it was necessary to raise the fundamental questions of being.
Descartes chooses to present his thoughts as meditations; he represents himself as seated before a fire in a cozy Dutch dwelling, wrapped in his dressing gown, freed from worldly care, and ready to devote himself to a task to which he had for some time looked forward, a kind of mental housecleaning. On six successive days, he pursues his meditation, step by step, clearing his mind of all error.
In Discours de la méthode (1637; Discourse on Method, 1649), Descartes reveals that the work was actually composed in very similar circumstances. In 1628, Descartes was in his thirties and living in Holland; he had withdrawn from a more active life for the special purpose of carrying on his philosophical and scientific investigations. Meditations on First Philosophy was circulated in manuscript, and when it was published in 1641, it included a lengthy appendix composed of objections by leading philosophers—including Thomas Hobbes and Pierre Gassendi—together with Descartes’s replies.
The First Meditation
The First Meditation is, in a way, distinct from the rest. It describes Descartes’s effort, which in fact engaged him for many years, to accustom himself not to think of the world in the imagery of the senses or according to the notions of common sense and the traditions of various schools of thought.
Can it be, Descartes wonders, that all beliefs that he had formerly held are false? Perhaps not, but if he is to achieve his goal of building up a body of incontrovertible truth, he must exercise the same rigor toward beliefs that are merely uncertain as toward those that are demonstrably untrue. That is to say, he must make doubt his tool. Instead of allowing it to hang over him, forever threatening, he must grasp it firmly and lay about until he has expunged from his mind every pretended certainty.
The first to go are those beliefs that depend on the senses—notably one’s belief in the existence of one’s own body and of everything that appears to the sight and touch. One’s habitual judgment protests. What can be more certain, Descartes asks himself, than that I am seated by the fire holding this paper in my hand? However, he writes, when one reflects that one’s dreams are sometimes attended with equal confidence, one is forced to conclude that there is no infallible mark by which one can know true perceptions from false.
Of course, what one doubts is, in this case, only that one’s ideas represent something beyond themselves. Descartes is one of the first philosophers to use the word “idea” in the modern sense. He means by it “whatever the mind directly perceives.” However, he distinguishes between the idea taken only as a mode of thought and the idea as a representation of reality. Even in dreams, one cannot deny the former. What one challenges is the “truth” of the ideas—Descartes calls it “objective reality”—and of judgments based on them. His question is whether there is anything in sense-images that testifies unmistakably to the truth of what they represent. Obviously not in those that one initiates in dreams and fantasies, and no more, he argues, in those that come from without, through the senses, or else how could one make mistakes as to sounds and sights?
There is, he says, another class of ideas that one seems neither to originate nor to receive from without but to be born with—those, for example, that make up the science of mathematics. Two plus three equals five, even in dreams, for this sum does not require material counters to make it true. Yet, the ideas of numbers profess to be something besides modes of thought. They do have “objective reality.” However, people...
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