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Thursday, April 28

April 28, 2016
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WWTWWT: Talked about Descartes, whom we can rightfully call the first modern philosopher. He, like many philosophers who lived and worked in France at this time, was a rationalist. He was also a brilliant mathematician, which explains his attraction to rationalism. Specifically, we discussed his most famous book, Meditations, the philosophical hole he dug for himself, and how he attempted to get out of it.

1. The Dream Argument. Descartes wanted to find out what it was we could know for certain. To figure this out, he had to first discard everything he felt he could NOT know for certain. He noted that it is often difficult to determine whether we are dreaming or awake. We can even, at times, feel what seem to be physical sensations — heat, cold, etc. — in dreams. The example he used was dozing by the fire and feeling its warmth in a dream.

Therefore, Descartes — like any good rationalist (including, to some extent, Plato) — discounts the evidence of our senses as something we can be sure about.

2. The Deceiving God Argument. After discounting the evidence of our senses, Descartes digs the hole even deeper. How do we know that everything we perceive isn’t just an illusion, the work of a God who, perhaps for good reasons, chooses to deceive us about the nature of reality?

3. Descartes’ Demon. It gets even worse. What if the illusions has been created by an evil demon, for the express purpose of tricking us? (Cue maniacal laughter.)

Image result for demon

Here’s where Descartes starts to climb out of the pit, by uttering one of the most famous phrases in philosophy history: “Cogito ergo sum,” or, “I think; therefore, I am.” In other words, the fact that he is able to have thoughts — whether they’re dreams or reality — is proof enough that he exists.

Descartes eventually makes it out of the pit, but he has to do so with God’s help. The next step is determining whether there is, in fact a God. Descartes says there is; to prove it, he resorts to the “ontological” argument used by the medieval philosopher St. Anselm. (He’s in your book.) This argument goes: think of the most perfect being possible. If this being doesn’t exist, then it can’t be perfect. Therefore, God exists. (The fact that we, as imperfect beings, are capable of imagining a perfect being, is also taken as proof that such a being exists — our imagining is thought to be the “imprint” of that perfect being on our consciousness.)

If such a perfect being exists, Descartes’ theory goes, he wouldn’t try to trick us. (Such deception would be “imperfect.”) Are therefore, in the end, Descartes concludes that we CAN, in fact, trust our senses. And thus, he emerges from the pit.

However, that’s a lot of help from God, as you can see. And if God’s existence is called into doubt — and it was, by those unconvinced by the ontological argument — then it’s hard to see how we can really know much more than the fact that our minds exist.

It’s also a limiting theory, in the sense that knowing the contents of our own minds — but not being sure about much of anything else — means we’re kind of stuck being unconnected minds, without any hope of really connecting with anyone else.Our minds and bodies are also forever separate in this theory — which is known as Cartesian dualism. The old mind/body split that Plato talked about has just gotten a lot wider.

Plato said the mind is trapped in the body, but he at least conceived of universals, which we could all agree upon, and which would therefore connect us. These aren’t really possible in Descartes’ theory.

Neither are they possible in the thought of John Locke, the British empiricist who responded to Descartes’ argument years later by trying to figure out the same thing: what can we really know for sure? Locke believed that “nothing could first be in the mind that wasn’t first in the senses.” Only sensory evidence was admissible here.

We looked at an Expo marker and tried to figure out what we could know about it. We can measure it, we can observe that it has a separate cap, and we could (if we had the means) break it down into its component chemical parts. Those are all what Locke would call “primary qualities” of the pen — quantifiable properties that everyone can agree upon.

Then we could talk about what color it is, and what it smells like. Those are what Locke would have called “secondary qualities,” because they depend on the perception of the person observing them. (Today, scientists call them “qualia” or “quale” in the plural.) However, Locke insisted that these qualities don’t exist in the object itself — they exist only in the minds of those perceiving the object. I see a blue pen, but someone else sees a purple pen. I smell fruit, you smell ammonia. The difference can be explained this way, by Locke and other empiricists: that there is no “blueness” or “fruitiness” that exists in the pen itself — those qualities are a function of our individual perception. If you and I both say we see a blue pen, there’s no objective way to know whether we are really talking about the exact same color. And there’s no way to do this because we have abandoned the concept of universals — that there is a thing called “blue” that we can all agree upon.

Because these “secondary qualities” exist in our minds, then, we have here another (though very different) example of Cartesian dualism. The mind and the body are separated, and there’s no real way for them to communicate. Locke ran into the same problem when he tried to describe what an object really IS, apart from its observable characteristics. Take away the measureables (its length, its width) and its sensory details (what color is it? how does it smell?), and what is it, really? We can’t really know this, according to Locke. It is, in his famous phrase, ” a something, I know not what.” (He called it “matter,” ultimately, but we know there’s no such thing as matter without form. But we can’t talk about form anymore, either! That got thrown out with Aquinas and Aristotle.)

In the same way that we cannot know what an object truly is, we really can’t know what we are, either. We can describe ourselves in terns of measureables, sure. And we can certainly (or hopefully!) remember all the experiences we’ve had, that have provided us with the sensory data that is the basis of our knowledge. But what are we, really, underneath all that? We can’t know, according to Locke. That is another important epistemological limit — a limit on what we can learn with any certainty.

No assignment for Tuesday, other than to re-read the sections on Locke and Berkeley in your book. The more you do it, the better chance you’ll have of understanding.

Book History: 

Siren: May stuff.

Also, remember what we were talking about Tuesday? Toldja.

Prompt: Notebooks were checked.  

Survey: CNF: We worked on (very rough) illustrated versions of opinion pieces. The goal was to get you to keep thinking about 1) moments, moments, moments, and what they look like, and 2) what it is you want to say in your essay.

These opinion essays are due a week from today: next Thursday, May 5.

I am also extending the deadline for the Mr. DeFade revisions: they are due (for both Survey classes) on May 5 as well.

Survey: Screenwriting:

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