Summary: Meditations on First Philosophy (page 2)
However, a counter-argument arises: is the body not more knowable than the mind or thought?
The body is visible; we can touch it, manipulate it, and conduct experiments on it.
Thought, on the other hand, is immaterial, and its nature seems mysterious.
Does Descartes, then, make a mistake in seeking certainty in the thinking thing? Should it not instead be sought in matter?
To refute this argument, Descartes, in Meditations on First Philosophy, presents the famous example of the wax. When we examine this piece of pure matter, we observe certain characteristics: a particular shape, consistency, colour, and so on. However, when heated, all these attributes, which seemed firmly anchored in the object, disappear. The solid wax becomes liquid; its colour, weight, and size change.
We had not, therefore, discovered an indubitable truth. It is thus illusory to seek certainty in matter and bodies.
Perception, which appears to grant us direct and immediate access to the truth of things, is ultimately deceptive.
By contrast, this truth can be discovered not through perception but through understanding. Indeed, in both solid and molten wax, there remain elements that do not change: wax always has a certain extension, a certain flexibility, and so on. These are invariant properties of any material object, grasped through abstraction. By abstracting the common features of different instances of extension, we arrive at the general notion of extension itself.
Thus, unlike perception, the intellect apprehends a truth within the thing itself. Here, Descartes anticipates the distinction that Locke will later draw between primary and secondary qualities in his Essay Concerning Human Understanding.
He provides a second example—the hats observed from his window—to illustrate that the intellect grasps a truth that escapes perception: the passers-by wearing these hats.
Descartes concludes that indubitable truth lies with the mind rather than the body:
From the fact that bodies themselves are not properly known by the senses or the faculty of imagination, but by the understanding alone, I see clearly that there is nothing that is easier to know than my mind 1.
In Book III of the Meditations on First Philosophy, Descartes seeks to deduce certain truths contained within the cogito. From the cogito, he has already derived truths about the self as a thinking thing.
For Descartes, we can also deduce certain truths about God from the truths he has uncovered about the self.
In other words: from the cogito, he deduced the self; from the self, he will deduce God.
This is a crucial point because until we know whether God exists—and whether he is not deliberately deceiving us about everything—we cannot be certain of any truth concerning the world.
To establish this, Descartes starts from the ego as a "thinking thing," the one indubitable truth. Now, this thinking thing contains ideas. He distinguishes between ideas "born with me," "produced by myself," and "foreign, coming from outside."
But how can we be sure that the latter refer to an external reality? After all, it is possible that I possess a spontaneous power to generate these ideas without any external influence, as in the case of dreams.
Descartes proposes a way to determine whether a particular idea truly corresponds to an external reality. This consists in observing that some ideas contain more degrees of being or perfection than others
2. He illustrates this with the distinction between the ideas of substance and accident: the former has more reality than the latter.
If we accept this principle, then we must acknowledge that the idea of God holds a unique status:
That by which I conceive a sovereign, eternal, infinite, immutable God certainly possesses in itself more objective reality than those by which finite substances are represented to me 3.
1 p.108
2 p.120
3 Ibid.