Why Does Descartes, in Meditation 1, Need the Dream Argument to Show That He Cannot Trust the Deliverance of His Senses If He Already Has Established That His Senses Sometimes Deceive Him?
René Descartes, in his work of Meditation on First Philosophy, sets the foundation for modern philosophy. Through the distinct style of writing in first person narrative, Descartes introduces radical skepticisms, proves the existence of God, distinguishes the soul from the body, and establishes levels of certainty in knowing the material world. With the Meditations intending to be a guide to exercising intellectual understanding and practice, there is a strong connection between the literary form and philosophical content, as one supplements the other.
Descartes begins the First Meditation by noting that there are many things he once believed to be true that he has later learned were not. This leads him to worry which of his other beliefs might also be false. So he sets out to “tear down” his existing set of beliefs and to “rebuild” them from scratch. For this he needs a solid “foundation,” i.e., some beliefs that simply cannot be doubted. If he can find something absolutely certain to serve as an “epistemic foundation” (i.e., the foundation for all his beliefs), he then can begin building a new structure. So, Descartes is searching for something certain, something that cannot be doubted. In order to find this kind of certainty, he sets out to doubt everything he can. It is not that he believes that everything he now doubts will subsequently turn out to be false, but rather this is the technique he employs to find something that is truly “indubitable.” This technique of doubting everything possible in order to search for certainty is known as his “Method of Doubt.” It consists in “withholding belief” from everything that even might be false. Given that Descartes has indefinitely many beliefs, calling each of them into question one by one would take forever, so he instead tries to cast doubt on an entire source of beliefs, namely, the senses. Is it possible that the senses, as a whole, are an unreliable source of information? This might seem implausible at first blush, given how much confidence we typically have in our own sense experiences. So, he attempts to undermine this confidence in a number of successively stronger challenges to our justification in believing what our senses tell us.
In an era of great debate over the fundamental facts of nature—e.g., about the Earth’s place in the cosmos, the amount of energy in the universe, the circulation of blood in the human body—René Descartes’ (1596-1650) central goal was to establish a body of scientific knowledge that held the same degree of certainty as mathematical truths.[Cottingham, John, 1984]The Meditations on First Philosophy (1641) is a classic work that lays the philosophical foundations of this enterprise.[Francks, Richard, 2008] It raises timeless and fundamental philosophical questions about knowledge, the self, the mind and its relation to the body, substance, causality, perception, ideas, the existence of God, and more. This two-part essay reviews Descartes’ process of reasoning and some of his arguments on these issues.
In brief, with this in mind, it is possible to assume that the work Meditations on First Philosophy can be taken as the attempt to introduce the main ideas of critical thinking. Thus, Descartes also tries to show people the way in which they could understand their human nature and assure that God really exists. Being reflection of Descartes vision of the world, the given work introduces a new philosophy which helps people to obtain some answers.
Cottingham, John, Robert Stoothoff, and Dugald Murdoch. Eds. and trans. The Philosophical Writings of Descartes (Cambridge University Press, 1984), vol. 2.
Francks, Richard. Descartes’ Meditations: A Reader’s Guide (New York: Continuum, 2008).