1. Descartes, Meditations 1 and 2
Monday, October 24th

2. Descartes mission
In his Meditations 1 and 2, Descartes sets out to find indubitable truths.
This means he sets out to figure out what things are true that are beyond doubt.
He calls this work his Meditations because he sets out to do this philosophical work purely by thinking about things (ratiocination).

3. Descartes mission continued
He wants to figure out what he can believe by discounting what he can possibly doubt.
That doesn’t mean he doesn’t believe in that which he finds he can doubt—he states that common sense beliefs don’t just go away.
But, philosophically, he wants to figure out what can’t be doubted; he wants to figure out what, if anything, is immune from skepticism.

4. On the senses
Descartes spends a considerable amount of time discussing how the senses mislead us—or can mislead us. We will talk about this more when we cover perception.
We’ve surely all had experiences of this. For example: thinking that you saw someone you know when it was actually a stranger.

5. On the senses continued
Although Descartes acknowledges that doubting the senses seems crazy to our common sense, we have philosophical reasons not to think that beliefs gained through the senses should be thought of as indubitable.
Sure, it feels to him like he is sitting in his dressing gown, being warmed by the fire, but he can’t believe this without the possibility of doubt.

6. It is important to note that Descartes thinks that knowledge is incompatible with the possibility of doubt. So, while we might have some common sense belief based on our physical senses, if we can doubt it, it can’t properly be called knowledge.
This relates to our discussions of justification. Certainty helps to justify beliefs, making them count as knowledge. The specific view is called “infallibilism”.
This type of view is less popular in epistemology today.

7. Skeptical hypothesis: dreaming
Descartes notes that although it feels very much like he is in a particular situation—sitting by the fire, writing—he has often had dreams which were just as vivid.
In dreams, we feel like we are having the same sorts of sensory experiences as we have in life.
If we were dreaming, we would have no way to tell! There is no way for him to prove to himself that, at the moment, he is not in a dream.

8. Consequences
“truths” discovered by physical sciences are questionable, and thus are not indubitable truths.
In contrast, the truths of math and geometry, being not dependent upon physical objects and the senses, seem to be in a different class.
But, Descartes thinks we can still be skeptical of these truths as well!

9. Skeptical hypothesis: deceitful ‘God’/ malignant demon
It is commonly believed that God is a good and all powerful Deity (as per Mackie’s paper).
Yet, it seems that we are sometimes deceived, and this seems to run contrary to God’s goodness.
And if we know we are deceived sometimes, what’s to make it the case that we are immune from constant deception? Couldn’t this be the case? How would we even know?

10. Deceitful God/ Malignant demon continued
Rather than doing what one normally does, treating one’s common sense beliefs as true, Descartes is setting out to do the opposite. He is trying to doubt everything.
He is entertaining the possibility that a malignant demon takes the place of God, and has employed its power to constantly deceive. This would make all of his common sense beliefs false (similar to the brain in a vat thought experiment).
By doing this, Descartes thinks he can arrive at conclusions regarding what, if anything, is beyond doubt.

11. Meditation 2: the nature of the mind, and its being distinct and more easily known than the body.
His previous discussion has him pretty freaked out, and he is very intent on arriving at something which can be said to be known—that is, that is beyond doubt.
“I suppose, accordingly, that all the things which I see are false (fictitious); I believe that none of those objects which my fallacious memory represents ever existed; I supposed that I possess no senses; I believe that body, figure, extension, motion, and place are merely fictions of the mind. What is there, then, that can be esteemed true? Perhaps this only, that there is absolutely nothing certain” (7).

12. Meditation 2 continued
Note: Descartes possesses doubts about all that is physical: physical objects, information gained through the physical sense organs, etc.
So, we can see him leading up to the distinction between mind (or soul) and body.

13. Meditation 2 continued
Descartes notices, though, that when he is doubting the existence of physical things some thing always remains—and that is that he is performing a mental action that is doubting.
In doubting we are doing something—namely, enacting our minds.
So even in the face of skepticism, there is a thinker doing the thinking, and thus there is something that exists.
“…I am, I exist, is necessarily true each time it is expressed by me, or conceived in my mind” (7).

14. Meditation 2 continued
So, Descartes knows that he exists, since even in doubting everything else one cannot doubt that he is doing the doubting.
But what is this doubting thing? What is he?
He used to think he was a man, but what is a man? Surely it can’t have anything to do with the body, for we saw that the existence physical is not indubitable.

15. Meditation 2 continued
What are we left with, if we discount the necessity of bodies?
We are left with thought.
Thus, Descartes can be certain that he is, at least, a thinking thing.
“But what, then, am I? A thinking thing, it has been said. But what is a thinking thing? It is also a thing that doubts, understands, [conceives[, affirms, denies, wills, refuses; that imagines, also, and perceives” (9).

17. The distinction between mind and body
We can see now why Descartes would be a dualist. That is, thinking that there are two types of substances in the world: the mental and the physical. Because the mental is indubitable and the physical is not, they can’t really be the same thing! Plus, it was commonly held that people had non-physical souls in Descartes’ time.
In opposition to this would be monism: the view that there is only one type of substance in the world.

18. What do we think?
Are his arguments persuasive? Do we have reason to doubt all that he says we should? Can we really be certain that our thinking is actually not just a deception? Wouldn’t a skeptical hypothesis cover everything?