Descartes' First Meditation: Doubt As A Foundation

In the first meditation of Meditations on First Philosophy, Descartes reflects on the falsehoods he has believed during his life and the faultiness of the body of knowledge he has built up from these falsehoods. He resolves to sweep away all he thinks he knows and to start again from the foundations, building up his knowledge once more on more certain grounds.

He reasons that he need only find some reason to doubt his present opinions in order to prompt him to seek sturdier foundations for his knowledge. He realises that if he were asleep and dreaming, many of his beliefs would be false. Since he cannot ever tell if he is dreaming or not, this is further reason to doubt any beliefs from his senses.

He also realises that he could be mistaken even about beliefs that seem clearly true to him, whether awake or dreaming, for example, that bachelors are unmarried. He could be mistaken, even about such beliefs, because he could be being deceived by some evil genius or even God: this is possible and he cannot show that it is not his actual situation. Since Descartes wishes to reject any belief that could be false, that he could be mistaken about, he rejects even these beliefs.

By the end of the first meditation, Descartes is tempted to rid himself of the desire to acquire knowledge altogether.

The senses can be deceptive

In his Meditations on First Philosophy, René Descartes argues that the senses do not accurately help us understand the world. He writes that he has begun to doubt all of his ideas, deciding that all those ideas come from the senses, which are not trustworthy.

Descartes' Dream Argument states that he often dreams of things that seem real to him while he is asleep. In one dream, he sits by a fire in his room, and it seems he can feel the warmth of the fire, just as he feels it in his waking life, even though there is no fire. The fact that he feels the fire doesn’t really allow him to tell when he is awake and when he is dreaming. Moreover, if his senses can convey to him the heat of the fire when he does not really feel it, he can’t trust that the fire exists when he feels it in his waking life.

In the Deceiving God and Evil Demon arguments, Descartes suggests that, for all he knows, he may be under the control of an all-powerful being bent on deceiving him. In that case, he does not have a body at all but is merely a brain fed information and illusions by the all-powerful being. Descartes does not intend these arguments to be taken literally. His point is to demonstrate that the senses can be deceived. If we cannot trust our senses to convey true information about the world around us, then we also can’t trust deductions we’ve made on the grounds of sense perception.

Descartes' Wax Argument also proves that the senses do determine traits of a substance but do not determine the nature of the substance. When one describes something, the senses offer clues to how one can describe it. Descartes describes the wax, and he gains the knowledge of these characteristics by using his senses. He knows it smells like honey because he is able to smell it. This idea goes for all the other characteristics and the corresponding sense. Descartes argues that the senses give one the image of an object, but not the knowledge of what that object truly is. The argument of the wax continues by Descartes heating the wax. The wax loses those characteristics that are sensed. This argument proves that the senses do determine traits of a substance but do not determine the nature of the substance.

Descartes' arguments illustrate that the senses can be deceptive.

The dream argument

In his First Meditation, Descartes reflects on the number of falsehoods he has believed during his life and the faultiness of the body of knowledge he has built up from these falsehoods. He resolves to sweep away all he thinks he knows and to start again from the foundations, building up his knowledge once more on more certain grounds.

In this pursuit, Descartes acknowledges that his senses can deceive him, but only with respect to objects that are very small or far away. He concedes that insane people might be more deceived, but he is clearly not one of them. However, he realises that he is often convinced when he is dreaming that he is sensing real objects. He feels certain that he is awake and sitting by the fire, but reflects that often he has dreamed this very sort of thing and been wholly convinced by it.

Descartes concludes that even if his present sensations are dream images, they are drawn from waking experience, much like paintings. Even when a painter creates an imaginary creature, like a mermaid, the composite parts are drawn from real things—women and fish, in the case of a mermaid. And even when a painter creates something entirely new, at least the colours in the painting are drawn from real experience. Thus, Descartes concludes that, though he can doubt composite things, he cannot doubt the simple and universal parts from which they are constructed like shape, quantity, size, time, etc.

However, Descartes realises that even simple things can be doubted. An omnipotent God could make even our conception of mathematics false. Descartes argues that God is supremely good and would not lead him to believe falsely in all these things. But by this reasoning, Descartes notes that God would not deceive him with regard to anything, and yet this is clearly not true. If there is no God, then there is an even greater likelihood of being deceived, since our imperfect senses would not have been created by a perfect being.

Descartes' argument, known as the "Dream Argument", has become one of the most prominent skeptical hypotheses. It raises the question of whether it is possible to ever be certain, at any given point in time, that one is not, in fact, dreaming, or whether it is possible to remain in a perpetual dream state and never experience the reality of wakefulness at all.

The evil demon argument

In his First Meditation, Descartes introduces the idea of an 'evil demon' as a device to subject all beliefs to rigorous sceptical doubt. He reasons that a demon intent on deceiving could easily make it appear to Descartes that he is sitting by the fire, even if this was not the case. If Descartes' sensory experience of sitting by the fire could be caused by an evil demon, Descartes does not know that he is sitting by the fire.

The evil demon is also known as the 'Deus deceptor', 'malicious demon', or 'evil genius'. It is an epistemological concept that features prominently in Cartesian philosophy. In the first of his 1641 Meditations on First Philosophy, Descartes imagines that a malevolent God or an evil demon, of "utmost power and cunning has employed all his energies in order to deceive me". This malevolent God or evil demon is imagined to present a complete illusion of an external world, so that Descartes can say, "I shall think that the sky, the air, the earth, colours, shapes, sounds and all external things are merely the delusions of dreams which he has devised to ensnare my judgement. I shall consider myself as not having hands or eyes, or flesh, or blood or senses, but as falsely believing that I have all these things."

The evil demon hypothesis is an important component of the Method of Doubt. Descartes used the Method of Doubt to find what is true by withholding assent from all beliefs that are dubitable. The Method of Doubt is destructive, not constructive, and aims to destroy and rebuild our knowledge on firm foundations. Once Descartes used the Evil Demon Hypothesis, he was able to remove all prior beliefs, which left him with a starting point from where he could rebuild all true knowledge.

The evil demon is also mentioned at the beginning of Meditation Two. Descartes says that if there is "a deceiver of supreme power and cunning who is deliberately and constantly deceiving me" then he himself must undoubtedly exist for the deceiver can "never bring it about that I am nothing so long as I think that I am something".

The evil demon hypothesis is not to be confused with the deceiving God argument, which is also present in the Meditations. Some writers make no distinction between the two, while others insist that it is important to maintain the distinction. Descartes himself, in the First Meditation, introduces the deceiving God argument before the evil demon hypothesis.

The existence of God

In his Meditations on First Philosophy, René Descartes attempts to establish what can be known for sure by discarding all belief in things that are not absolutely certain. In the third meditation, Descartes turns his attention to the existence of God.

Descartes begins by classifying his thoughts into three types: images or pictures of things (ideas), thoughts that represent particular things and include more than just the likeness of that thing (volitions or emotions), and thoughts that represent particular things and include a judgment about them (judgments). He argues that only judgments can be false, as the other two types of thoughts are either true by virtue of being imagined or are true desires or emotions.

Descartes then turns to the origin of ideas. He identifies three types of ideas: innate ideas that have always been within us, fictitious or invented ideas that come from our imagination, and adventitious ideas that come from experiences of the world. He argues that the idea of God is innate and placed in us by God, and rejects the possibility that such an idea is invented or adventitious.

Descartes then presents several arguments for the existence of God. Firstly, he argues that something cannot come from nothing, and that the cause of an idea must have at least as much formal reality as the idea has objective reality. As he has an idea of God, and this idea has infinite objective reality, he cannot be the cause of this idea as he is not an infinite and perfect being. Therefore, there must be a being with infinite formal reality that caused this idea—God.

Secondly, Descartes argues that an absolutely perfect being is benevolent. As God is perfect, he does not deceive human beings, and therefore, because God leads humans to believe that the material world exists, it does exist.

Thirdly, Descartes argues that his existence must have a cause. This cause cannot be himself, as he did not create himself, nor can it be something less perfect than God. Therefore, the cause must be God.

Finally, Descartes argues that the idea of God could not have originated from himself, as he is finite, and the idea of God includes that of infinity. This idea must, therefore, have come from a substance that itself is infinite.

Descartes concludes that God necessarily exists.

The nature of the human mind

In the Second Meditation, Descartes attempts to find something certain, or to become certain that there is no certainty. He begins by supposing that everything he sees is fictitious, and that his memory tells him nothing but lies. He has no senses, and body, shape, extension, movement and place are illusions.

However, he still exists, and is a thinking thing. He has a clear and distinct idea of himself as something that thinks and isn't extended, and one of body as something that is extended and does not think. He concludes that he is really distinct from his body and can exist without it.

He also has faculties of imagination and sensory perception. He can clearly and distinctly understand himself as a whole without these faculties, but he can't understand them without him. He is a substance, and faculties are properties or powers of it.

Descartes concludes that the mind is better known than the body, and that the mind is more known than the body.

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