THE SECOND MEDITATION: I THINK THEREFORE I AM
“The first precept was never to accept a thing as true until I knew it as such without a single doubt.”
Le Discours de la M?thode, I
In the First Meditation, Descartes invites us to think skeptically. He entices us with familiar occasions of error, such as how the size of a distant tower can be mistaken. Next, an even more profound reflection on how dreams and reality are indistinguishable provides suitable justification to abandon all that he previously perceived as being truth. (18, 19) By discarding all familiarity and assumptions, Descartes hopes to eliminate all possible errors in locating new foundations of knowledge. An inescapable consequence of doubting senses and prior beliefs is the introduction of the possibility that God is in fact a malicious deceiver, an all-powerful being capable of confounding the senses. (22)
As the Second Meditation begins, Descartes again faces the “inextricable shadows” brought forth by the previous day’s thoughts. (24) He continues to disregard anything that “admits the least doubt” – including all that is perceived by the senses – since anything that is tainted with doubt might as well be considered totally false. (24) However, once an element of truth is discovered and verified, it can be used as a basis for establishing other elements of truth.
The first element of truth that is known for certain is that nothing can be confidently known. Such a statement has a curious sort of circular nature: how can I know that nothing is certain, if nothing can be known for certain? The answer simply contains itself in the definition. By knowing that there is nothing for certain, Descartes must abandon all that is reported to him by his senses and believed by him in his thoughts (including his body and the conception of the world around him). (24) At this point, Descartes is not prepared to accept that either himself or God exists. He cannot say that God exists, because there remains the possibility that his thoughts are in fact originating from himself (in which case there would be no need for God). Since he has abandoned all notions of existence and certainty, which includes his own body and senses, is it possible that he himself does not exist? To think a thought is bound to existence by definition; one must exist first before having the ability to think. Even if an all-powerful deceiver made it so that I do not exist, it would generate a contradiction since I cannot think that I exists if I don’t. (25) Thinking about existing requires existence as a prerequisite. Descartes has arrived at his first truly tangible and useful element of truth: that it is necessarily true that he exists.
The next task that Descartes must consider is to define what he is, and in doing so be careful not to make assumptions. He cannot consider himself to be an animal, since that would require a definition of what an animal is. Such an examination is beyond the discussion. (25) Instead of making random guesses, Descartes begins to think about what came to mind when he considered what he was. (25, 26) The first thought that occurs to him is that he has a body – something that by definition has a determinable shape, defined location and that can occupy space. However, if an all-powerful deceiver is at work, then that which he perceives as being his body might be something else altogether. Without a body, the attributes that would have naturally followed from it’s definition – that he must be nourished, that he changes position and that he engages in sensory perception – must all be discarded. (27) In a flash of inspiration, Descartes realizes that ‘thinking’ is the quantity that is inseparable from existence. He will exist for as long as he is thinking, and for the duration of his existence, he will remain a thinking thing. Thinking is the ability to doubt, affirm, deign, act on will, and use imagination and sensory perceptions.
When Descartes affirms that he exists, he recognizes that his existence cannot depend on anything that he could “feign in [his] imagination”. (28) The word ‘feign’ is at the root of the potential error; to feign an idea is to invent it. So it is clear that the things that are thought of in the imagination are inherently fictitious. Imagining something tangible (or “corporeal”) is to perceive its “shape or image”. (28) Such images could be dreams, so it is clear that using the imagination to establish truths is a flawed approach. Imagining one’s existence is as useless and flawed as choosing to enter a dream in order to better understand something that was seen in reality.
What is the purpose of this dialog that Descartes is having with himself? It is more then an invitation to philosophical reflection, since he is encouraging his readers to follow along and conduct the arguments with him. Descartes is guiding the reader to discover purely intellectual conceptions of mind, matter and God. The ultimate goal is a true, unpolluted view of the world. In Descartes’ view, the only way to arrive at true conclusions is to begin with premises that are never false. By this method, one starts by accepting nothing as being true – even those things that we would never think of questioning. If one thing can be found to be true, it can be leveraged and used to build a strong foundation for knowledge. In the Second Meditation, Descartes sets out to prove that the pinnacle truth is that he exists. At first, this truth must be disconnected from other perceptions and thoughts, such as those conjured by the senses (his body, and the world around him). The next realization is that his existence is connected to thinking, since thinking cannot be accomplished without existing and vice versa. Therefore he is a thinking thing. Finally, Descartes is careful to point out that even though imagination is an ability granted to him by virtue of the fact that he is capable of thinking, it should not be used to further the investigation at hand. Such abstinence is justified because things perceived in the imagination are likened to things perceived in dreams, and are subject to falsity or malicious tampering by an all-powerful deceiver. All of this sets the stage for subsequent meditations in which Descartes will attempt to prove the existence of God and acquit her of malicious intent.
All page references are to Descartes, Rene, “Excerpts from ‘Meditations’” from Meditations on First Philosophy, Pp. 52-54; 57-67, ? Hachett, 1995.