Meditations on First Philosophy

Meditation II
Concerning the Nature of the Human Mind: That It is Better Known Than The Body

Descartes' Second Meditation is somewhat difficult, and at times it is not easy to keep track of what he is trying to do. Although Descartes' argument is not wholly clear (he never explicitly makes the connections that I will make, but rather implicitly points to those connections) the argument is capable of reconstruction.

First, note that Descartes has two main subjects in the second meditation, (a) the cogito (or the thinking thing) and (b)
the wax example. It's probably a good bet that these subjects are connected -- and they are.

I. The Cogito Arguments and Foundationalist Epistemology

Remember that what Descartes is looking for is certainly. This is what he claimed at the end of the first meditation he could not find (yet). Descartes is, epistemologically, a foundationalist. A foundationalist believes that for an agent to be in a state of "knowledge" requires that the agent be certain about something (we can leave open what that something is).

Descartes feels the same way.  In the first meditation when he argues that if we can doubt the foundations of a particular science, then all knowledge claims of that science are henceforth suspicious and possibly dubious, he is highlighting his foundationalism. Descartes' argument is somewhat like this:

1. The individual knows that X.
2. If the individual knows that X, then the individual knows X to be absolutely certain.
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3. Thus, the individual has 100% certainty in X's truth.

also:

1. The individual knows that X.
2. If the individual knows that X, then either (a) the individual knows X directly by intuition, or (b) the individual knows some other proposition Y directly by intuition, and Y implies X logically.
---
3. The individual either knows that X by intuition or knows some proposition Y by intuition and Y implies X logically.

Both arguments rely on foundationalism.

The first argument merely suggests that "knowing" is an absolute relation -- to know something is never to by 99% certain of it, but to be 100% certain of it. That's why -- no matter how "commonsensical" -- many of the beliefs Descartes questions in meditation I cannot be knowledge claims because they are logically doubtable (and so not 100% certain).

The second argument suggests that to know a proposition can only come in one of two ways. Either we intuit the proposition (a proposition that can be known by intuition is self-evidently true) or we know it by demonstration, a demonstration that must make use of at least one self-evident truth.

Here's an example:

1. I know this by intuition: "If X is bigger than Y, then Y is smaller than X."
2. Perhaps I also know this proposition: X is bigger than Y.
3. Then I can conclude by demonstration that Y is smaller than X, and be 100% certain, even though I do not know "Y is smaller than X" by intuition.

If foundationalism is true, then it will obviously be impossible for an individual to have any knowledge at all if that individual does not have a self-evident truth from which all the rest -- directly or indirectly -- rest. Descartes mentions this in the beginning of the meditation. He says:

Archimedes sought but one firm and immovable point in order to move the entire earth from one place to another. Just so, great things area also to be hoped for if I succeed in finding just one thing, however slight, that is certain and unshakable. (pg 30)

If Descartes can find this one certain truth, the rest of knowledge can use it as a foundation. Descartes calls this one truth the "archimedian point." What then is this point? For Descartes, it is the existence of the cogito, or the thinking substance. He reaches this point through the methodology of doubt.

The First Part of the Cogito Argument

1. I can doubt the reality of all of my bodily properties.
2. If I can doubt the reality of all of my bodily properties, I can exist without them.
3. Thus, I can exist without my bodily properties.

Second Part of the Cogito Argument

Recognizing at this point that "all that is left" of him is a thinking being, Descartes now wonders whether even the thinking part of him could be a deception. Could the evil demon fool him about his own existence at this level? Descartes says no.

1. If an individual doubts, then that individual is thinking.
2. Thinking, in each of its various modes (sensing, willing, reasoning, etc) is a property.
3. If a property exists, then it exists in a substance that supports it (This premise is assumed)
4. I am doubting.
5. Thus, I am thinking. [from 1, 4]
6. Thus, I am a substance which underlies the momentary thoughts I am having. [from 5, 2 and 3]

The undershot of this is: I think, therefore I am or cogito, ergo, sum.

Descartes' argument is to say: througout this exercise, I have been doubting everything. Doubt itself cannot be doubted, because it presupposes another act of doubt. So I can be intuitively certain that my own thought process exists. I cannot be fooled about this. Furthermore, if I am thinking, then I know -- because every property requires a substatum -- that I must exist as a thinking substance.

Descartes' argument here presupposes that we bring into light two theories about properties.

The Bundle Theory: According to bundle theory, a "thing" is really just a collection of properties that happen to be coexisting. The orange over there is nothing but orangeness, sweetness, roundness, and so on all existing in the same place. So according to bundle theory a thing isn't a bunch of properties adhering in a substance, it is just a bunch of properties in the same place/time location.

The Substance Theory: According to this view, a thing is composed of various properties plus an underlying substance to which these properties belong. So the orange isn't just those properties, but those properties adhering in a substratum. When we use common sense grammar our approach is usually substance theory.

"The sun is yellow" seems to predicate a property (yellow) of a thing. Surely what we don't mean by this is that a bunch of properties is yellow. We seem to be assuming in common sense grammar that there is a thing, and then there are properties stuck to that thing.

Descartes, in the Cogito Argument, endorses the Substance Theory. His argument implies it -- he is a thinking substance because he is certain that he is thinking, and thinking is a property. Descartes is thinking here that if there's a property, there must be a substance in which that property adheres. Now we know it can't be corporeal substance, because the first part of the argument has shown that the individual can exist without the body. So the substance that Descartes is referring to here must be a different kind of substance, namely, thinking substance.

Descartes notes that the mind, at this point, has a hard time keeping its eye on "non-corporeal" stuff. It has a hard time not dealing with the body and the imagination. So it easily falls from thought about the cogito and onto corporeal objects. So Descartes begins to talk about the "wax example." At first sight it may seem as if Descartes has changed the subject. But he hasn't. Instead, he is moving to an example in the corporeal realm that will support what he has already said abou the cogito.

Thus we can read the wax argument at the end of the meditation as an argument in favor of the Substance Theory, and that argument might be reconstructed thus: (thanks to George Dicker and Curtis Brown for the following references):

The Argument from Change

Descartes' discussion of the wax centers in on the claim that although a piece of wax might change all of its properties and take on new properties, it is still the same piece of wax.  In other words, Descartes seems to be suggesting that a thing is not merely the sum of its properties (which would be bundle theory). Throughout change, a thing can remain the same so long as what underlies the properties remains the same. This, of course, is substance. The first argument goes:

1. We can distinguish between (a) all of a thing’s determinate properties changing without the thing’s ceasing to exist and (b) a thing’s ceasing to exist. (We know that even though the wax has lost all of its original properties, it is still the same old wax).
2. We can distinguish between (a) and (b) only if a thing is composed, in addition to its properties, of a permanent, underlying substance. (If bundle theory was true, we could not "track" a thing over change).
3. So, A thing is composed, in addition to its properties, of a permanent underlying substance. (From 1, 2)

Argument from Intellection:

How do we do this -- track an object over time and change? Descartes seems to admit in meditation two that substance is not sensed. It is not sensed because it is not a property, and the senses recognize properties of things. So how in the world can we know that there is a substance there?

Since it is not sensation, Descartes wonders whether it is the imagination. He quickly rules this out, noting that the imagination makes use of images, and the images in the mind are taken from corporeal things (which requires sensation). In addition, Descartes notes that although we seem to know that the wax can undergo a staggering number of changes and still be the same wax, we cannot -- he suggests -- capture all of these possibilities in imagination. So the imagination cannot be the mental faculty that informs us of the existence of substance. When he discusses the wax, he says:

"It remains then for me to concede that I do not grasp what this wax is through the imagination, rather, I perceive it through the mind alone...But what is this piece of wax which is perceived only by the mind? Surely, it is the same piece that I touch, see, and imagine...but I need to realize that the perception of the wax is neither a seeing, nor a touching, nor an imagining. Nor has it ever been, though it previously seemed so; rather, it is an inspection on the part of the mind alone." (33)

Now that Descartes thinks he has proved that the mind "alone" has the power to "perceive" what the senses cannot inform us about, he naturally moves to the mind itself. How is it that we know that there is a substance behind all of our sensings, imaginings, and doubts? We can "perceive it by the mind alone." What Descartes is really saying here is that we can gain some knowledge of things by intuition.

We can consider the second meditation finished by bringing the points about the wax example back to the cogito argument, and see that it proves that we are thinking substances.

A Reconstruction of the Cogito Argument

1. A thing is composed of its properties or characteristics plus an underlying substance to which they belong (Substance Theory)
2. If there is a property or characteristic, then there must be a substance to which it belongs (From 1)
3. A thought is a property (Assumption)
4. If there is a thought, then there is a substance to which it belongs. (From 2, 3)
5. There is a thought (Assumption)
6. So, there is a substance to which this thought belongs: "I" (From 4, 5)