Literature Study GuidesMeditations On First Philosophy With Objections And RepliesFirst Meditation Of Those Things That May Be Called Into Doubt Summary

Meditations on First Philosophy (with Objections and Replies) | Study Guide

René Descartes

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Meditations on First Philosophy (with Objections and Replies) | First Meditation: Of Those Things That May Be Called into Doubt | Summary



The Meditator finds himself at a point in life when he can finally properly contemplate the epistemological problems that have plagued him for years. He has many beliefs that rest on shaky foundations. Specifically, beliefs grounded in sense experience, or inherited from tradition and authority, seem dubious. If these are doubtful, he wonders, what other beliefs might be doubted?

The Meditator resolves to cast aside his beliefs and start anew, seeking (metaphysical) certainty as the foundation for (scientific) knowledge. More specifically, he seeks to determine the principles upon which these beliefs are built. It is the senses—directly or indirectly—that have provided the ideas he believes to be true. These, then, should be doubted.

As the Meditator begins this procedure, he wonders if, perhaps, sense experience can be vindicated—surely there are some sense experiences that aren't deceptive, such as immediate sensations. For example, he wonders how it is possible to doubt he is sitting by the fire, reading, and that the hands he sees before him are his own. Only someone who is "mad" could doubt his own body.

Then again, he could be dreaming. Although he may not find reason to doubt his senses with regard to his immediate experience, he could in fact be dreaming. If this is the case, then he only dreams the sense experiences he believes cannot be doubted, in which case they can, in fact, be doubted. After all, "seeing" in a dream is not actually seeing. It is an illusion of sorts.

The Meditator decides not to worry about whether or not he is awake and instead supposes he is asleep. He wonders if he can still get at something that is indubitable. For example, images in dreams seem to represent real objects—or if they are fanciful images the colors seem real.

The Meditator continues in this vein, inferring from the seeming reality of colors to general ideas about objects. In other words, supposing dream images are fictitious, there could be—like colors—something real ("more simple and universal") underlying those images. So, for example, although Pegasus (a mythological winged horse) does not exist except in the imagination, winged creatures and horses do exist. Even more generally, even if winged creatures and horses are only dream objects, they could refer to certain elemental features of objects, such as extension, quantity, position, and duration.

Therefore, even if there are no objects to which the dream images refer, the underlying (mathematical) structure of those images should be real. As the Meditator asserts, "For whether I am waking or sleeping, two plus three equals five, and a square has no more than four sides."

But this certainty does not last, for the Meditator next wonders whether or not he is being deceived into thinking such certainty. Maybe this deceiver is God. Alternatively the Meditator believes himself to be fundamentally defective and prone to making errors. The Meditator reaches the conclusion that the idea of God as deceiver is false since God is thought to be supremely good—and he is not certain God even exists.

Still the Meditator could be deceived, if not by God, then by "some evil spirit, supremely powerful and cunning, [who] has devoted all his efforts to deceiving me." The Meditator resolves to assume this is the case. What follows is that he cannot believe anything at all is true—after all it is possible he is being completely, exhaustively deceived.

This radical doubt is, however, a "laborious" task, and the Meditator soon wearies. Lapsing into his former beliefs (such as that he has a body, and so forth), the Meditator ends his meditation.


It is worth noting the Meditator situates himself in the context of a life already lived. He is capable of "master[ing] the various disciplines." At the same time, however, the pressure of a lifetime of customary, traditional, and habitual beliefs complicates the undertaking. It is difficult, after all, to discern which ideas seem true simply because one is used to them and which are actually true.

The Meditator constructs a method in order to avoid error. This does not involve looking at each belief to determine whether or not it is false but instead focuses on the underlying principles of his beliefs. These are associated with sense perception, so the senses should be doubted. The supposition that some sense experience might be reliable is the first response to doubt, the first level as it were. In other words Descartes has set up an internal debate for the Meditator. On one side is the doubter, determined to eliminate all false beliefs from his inventory. On the other side is "common sense," that part of a person that finds relying on sense perception appealing.

This internal struggle proceeds by way of distinguishing those sense experiences that seem clearly problematic, such as those of relative size and distance. They are easily doubted since they conflict: the sun sometimes appears very small, while at other times it appears very large. The "immediate" senses, however, seem much more reliable. An examination of them leads the Meditator to some unpleasant conclusions.

Immediate senses are no different from the hallucinations of one who is insane. Consider, for example, the experience of hearing voices that aren't really there, or the phantom pain from a limb amputated long ago. The Meditator does not stop the analysis with mental illness but pushes it back into the realm of the ordinary by way of dreams.

Dreaming begins the second level of doubt. As with hallucinations, dreaming feels very real. The Meditator realizes that, if sense experience is the standard whereby a belief is judged to be true, then neither the mad man nor the dreamer can tell the true from the false. Doubt has taken an even stronger hold than it had at the beginning of the First Meditation. What has begun—and in what follows—is a picture of how difficult it is to overcome this doubt. Consider the nature of the doubt—it is not mere psychological uncertainty. This presses the Meditator onward.

One question that arises in the dream sequence is what sort of dream the Meditator is talking about. Does he mean to say he has no standard by which he can determine dreaming states from waking states? Or does he mean life itself could be a dream? In either case the main difficulty with which he is confronted is a lack of a reliable standard by which he can determine what is true. The Meditator asserts, "What happens in sleep does not appear so clear nor so distinct as does all this [looking at the paper before him, moving his head, extending his arm]."

The analysis of a dream's content reveals what seems to be a guaranteed truth: mathematics. Even if the content of the dream is fictitious, it cannot make a four-sided triangle. At the moment of this seeming certainty, the Meditator reaches a third level of doubt: deception.

At this point not only are beliefs based on sense perception called into doubt but also rational beliefs such as those involved in mathematics. The two initial explanations for the deception are rejected: the first that God deceives him into error; the second, if there is no God that he himself is the source of his errors. It is worth pointing out that setting the God question aside allows Descartes to clear more intellectual territory and establish its boundaries. He is not ready, in the construction of the larger argument, to argue for God's existence. It suffices for now to simply mention that, if there is a God, by definition he would not be a deceiver. The introduction of the evil genius preserves and enhances the possibility of deception and so deepens the doubt, while leaving the God question for later.

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