I Think, Therefore I Am... Real

The claim with which Descartes begins his second meditation - that the only unarguable truth is that nothing, in fact, is certain - brings forth memories of Socrates, who claimed, during his trial, that the only thing he knew for sure was that he knew nothing. For Descartes, however, the above statement is not the ultimate conclusion, but rather the fundamental point on the basis of which to develop his understanding of what we as humans indeed know. By deconstructing humanity's internal world (the body) and external world (the surroundings), Descartes finally arrives at the conclusion that one thing we know for sure is that we exist - hence, we are real - through the power of our intellect, and subsequently that the world around us exists - hence, is real - through our understanding (as opposed to sensory perception) of it.

Descartes' approach to reassuring himself and his audience of the reality of one's own existence, as well as that of the world around us, is to start with a 'clean slate', so to say, by denying the real existence of the world and of himself in it. By noting that his sensory perceptions of the world while awake and while sleeping are basically the same, and assuming (at that point in his argument) that only what he perceives while awake is real, Descartes claims that since it is impossible to distinguish between the states of sleep and wakefulness through one's sensory perceptions, it is thus impossible to distinguish between what is real and what is illusory. He assumes the existence of an "evil genius" of God-like powers, whose main goal is to deceive humanity into believing that themselves and the world around them are real. Descartes' approach, therefore, is to assume that everything is illusory, that both his body and the world around him are not real. He argues that this is the only way not to allow deception to influence his perception.

In his search for what is real, Descartes starts basically with nothing. He cannot rely on his senses because, with the body being only an illusion, none of the bodily senses can be claimed to exist. Even if it is to be assumed that they do exist, they are unreliable because of their propensity for being deceived. The only thing on which he can proceed is the fact that there is some entity, some form of self, on which influence is being exerted, both by the aforementioned "evil genius" that is trying to deceive it and by Descartes himself trying to convince oneself that he is being deceived. Since the acts of such influence do take place and are directed at something, it is thus impossible to claim that 'something' is, in fact, nothing.

Next, Descartes proceeds to determine what this 'something' actually is. He constructs a complex definition of the "body" and carefully evaluates it on the basis of his prior assumptions, finding, one by one, that none of these elements can be claimed to be real. It is only when he arrives at the concept of thinking that he makes his "discovery" that thought exists. Indeed, without thought, it is impossible even to presume that nothing else in the world really exists. From this, he generates the first 'real' definition of himself - that of "a thinking thing."

From this, Descartes proceeds to expand his reality. First, he reconstructs his own body by examining his senses not on a case-by-case basis, but rather in general. In other words, even though it is possible to assume that his senses can be deceived on individual occurrences, it is undeniable to Descartes that, in general, he can receive visual, auditory, and tactile stimuli because he can think he sees, hears, or has physical sensations. Essentially, Descartes arrives through logic at what science would later arrive through experimentation: that to which we generally refer as sensory perceptions are actually signals generated by our brain upon processing various external stimuli. In other words, just because one has eyes, ears, and tongue does not mean one can see, hear, and taste - one needs a brain to interpret the stimuli received through those organs.

Having established the reality of one's own body, Descartes proceeds to establish that of his surroundings. To do so, he uses the easily "mutable" material, namely wax, to show that the reality of a certain object or substance does not really depend on how we perceive it through our senses, but rather on how we understand it with our mind. Wax can be fragrant or odorless, white or colored, solid or liquid, but just because certain qualities or features that initially help us identify it as wax are lost, wax does not stop being wax to our minds. In Descartes' own words, "... I need to realize that the perception of the wax is neither a seeing, nor a touching, nor an imagining... rather it is an inspection on the part of the mind alone." We do not even need to see wax in front of us to know what it is - which, in Descartes' understanding, is exactly what makes it real.

Criticism of Descartes' approach can be made on the basis of cultural and cognitive relativism. Descartes makes his conclusions on the basis of his own mind - the mind that benefited from university education at one of the most prestigious schools in 17th-century France. Even among his European contemporaries, there undoubtedly were numerous individuals who could not perceive with their minds what Descartes could perceive with his - not to mention people from other, less developed cultures. These people's reality - on the basis of their intellectual perception - certainly was much different from Descartes' own. Furthermore, in hindsight, human knowledge in the 17th century precluded even highly educated individuals like Descartes from intellectually perceiving many of things we in the 21st century think of as a matter of fact. Just because Descartes, limited by his contemporary state of human knowledge, could not think of them did not make them any less real.