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Descartes: I Think Therefore I Am

by jduster
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DaveC426913
#37
Feb2-12, 08:11 AM
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Quote Quote by wuliheron View Post
You can also categorically state the moon is made of cheese, but I prefer evidence myself.
Then you're in the wrong discussion and possibly the wrong forum.

You'll have to rely on logic here. No evidence is going to be forthcoming. Not the least of reasons because the very discussion is that all evidence is suspect.
DaveC426913
#38
Feb2-12, 08:13 AM
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Quote Quote by ThomasT View Post

Back to Descartes. "I think, therefore I am" is a tautology.
No it isn't.

Quote Quote by ThomasT View Post
"I am" is a tautology. This follows from the definitions of the terms.
This is weak and Descartes rejected it. He knows it is a tautology.

Quote Quote by ThomasT View Post
We know that we exist via the conventional usage of those terms. There's no doubt, by definition.
So, if I define myself as stinking rich, I am?
Jimmy Snyder
#39
Feb2-12, 08:38 AM
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Quote Quote by DaveC426913 View Post
So, if I define myself as stinking rich, I am?
I stink. Therefor I am rich.
daveb
#40
Feb2-12, 09:07 AM
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Quote Quote by Jimmy Snyder View Post
I stink. Therefor I am rich.
I thought you were Jimmy?
ThomasT
#41
Feb2-12, 11:21 AM
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Quote Quote by DaveC426913 View Post
No it isn't.
Ok, I think I understand why it's not a tautology. "I am" is a tautology, but "I think" isn't a tautology, and "I am" and "I think" are not equivalent, but "I think" is a subset of "I am", so if I think, then I am, or "I think, therefore I am."

Now I have to go back in the thread and Google/Wiki/Stanford/whatever to understand why "I cook, therefore I am" doesn't work the same way. (As might be evident, I do a lot more cooking than thinking.)

Quote Quote by DaveC426913 View Post
This is weak and Descartes rejected it. He knows it is a tautology.
I was thinking that the statement "I am" is self-evidently true because of the conventional usage/meaning of the terms involved. That is, saying that I doubt or can doubt my existence would seem to be a contradiction in terms given what "my being", "my existence", "I am" refer to.

Quote Quote by DaveC426913 View Post
So, if I define myself as stinking rich, I am?
I was saying that "my being" or "my existence" refers to my subjective experience, which I have no doubt about experiencing.
wuliheron
#42
Feb2-12, 11:28 AM
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Quote Quote by DaveC426913 View Post
Then you're in the wrong discussion and possibly the wrong forum.

You'll have to rely on logic here. No evidence is going to be forthcoming. Not the least of reasons because the very discussion is that all evidence is suspect.
I beg to differ, the argument is about which types of evidence are less suspect then others, including what logical arguments.
Char. Limit
#43
Feb2-12, 11:30 AM
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"I think therefore I am" is definitely NOT a tautology. The two statements aren't even equivalent. The converse of "I think therefore I am", "I am therefore I think" is definitely not true for everything.
ThomasT
#44
Feb2-12, 12:20 PM
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Quote Quote by Char. Limit View Post
"I think therefore I am" is definitely NOT a tautology.
Yes, I see that now.

Quote Quote by Char. Limit View Post
The converse of "I think therefore I am", "I am therefore I think" is definitely not true for everything.
It's not necessarily true for anything, is it? That is, no particular mode of being is implied by being. Being doesn't imply thinking.

What I still don't get is why cooking doesn't imply being.
Char. Limit
#45
Feb2-12, 12:22 PM
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Well of course "I cook therefore I am" is a valid statement. But, like Descartes had to prove he was thinking, you have to, I guess, prove that you're cooking. Descartes' method of proving he was thinking was to assert that he is doubting, which implies thought.
ThomasT
#46
Feb2-12, 12:37 PM
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Quote Quote by Char. Limit View Post
Well of course "I cook therefore I am" is a valid statement.
That's what I thought.

Quote Quote by Char. Limit View Post
But, like Descartes had to prove he was thinking, you have to, I guess, prove that you're cooking.
How does one prove an experience?

Quote Quote by Char. Limit View Post
Descartes' method of proving he was thinking was to assert that he is doubting, which implies thought.
I still don't get it. Does counting imply thought? Why is doubting special? Why is thinking special? Why not just "I experience, therefore I am"?
ThomasT
#47
Feb2-12, 12:42 PM
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What do the words "being" and "existence" refer to? If the referent is our subjective experience, then I don't think that Descartes has proven anything beyond what's already evident.
Ryan_m_b
#48
Feb2-12, 01:21 PM
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Quote Quote by ThomasT View Post
What do the words "being" and "existence" refer to? If the referent is our subjective experience, then I don't think that Descartes has proven anything beyond what's already evident.
I'm not sure if he was trying to prove anything, rather he was pointing out that the only thing we can be certain of is our existence. Everything about that existence can be faked but the fact that there is an existence cannot: you can convince an extant being everything but you can't convince a non-existent entity of anything.

It might seem evident but evidently for many it isn't.
wuliheron
#49
Feb2-12, 01:57 PM
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Quote Quote by ThomasT View Post
What do the words "being" and "existence" refer to? If the referent is our subjective experience, then I don't think that Descartes has proven anything beyond what's already evident.
I don't believe proving anything new was the point to begin with. Descartes was attempting to create a new philosophical foundation upon which the emerging sciences of the day could distinguish themselves from the church. The issue was how to accomplish that while still working within the accepted cultural biases of the time. Hence, by focusing on the ego he found a way to exploit the dualistic bias of the culture and church to advance the sciences.
DaveC426913
#50
Feb2-12, 03:45 PM
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Quote Quote by ThomasT View Post
...I don't think that Descartes has proven anything beyond what's already evident.
'Evident' is not enough. It's based on an assumption. He rejected assumptions.

Descartes believed that everything was based on assumptions. He set out to prove that nothing could be said at all without basing it on some assumptions that itwas real. In a sense, he set out prove that our existence was a tautology.


Look at it from the other side of the coin. Assume absolutely everything is an illusion, craftily put in front of you. The world, everyone you know, your eyes, even your brain. All these things could be constructs, put in your mind to fool you into thinking they're "evident", as you call it. So we can trust none of them.

It's very Matrix-like.

But what Descartes realized is that, even if everything is an illusion, there is still something experiencing that illusion. Even if you Thomas, are a program in a computer, fed all your sensory input. There is still something that is experiencing that input.

No matter what it looks like, no matter what it's made of, it exists.

He is showing that your statement "I am" is not simply an act of defining something as existing, he can logically show it to be true.

...

I think I'm not really adding anything more to this thread except repeating myself.

Perhaps one thing to add:

...


These things are evident to us now. One big reason why is because people like Descartes did ground-breaking work that our knowledge is based on.

Perspective in artwork is self-evident in the modern world. We know objects that are farther away are smaller than objects nearby. But that wasn't self-evident before da Vinci and his contemporaries came along and defined it -took the mystery out of it - that it became self-evident after that.

There are other examples in science, such apples falling to the Earth and the correlation between force, mass and acceleration that we wonder how they could not have known them at some time in the past.
wuliheron
#51
Feb2-12, 05:36 PM
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Asians covered the subject thousands of years ago and took the opposite approach. Instead of assuming that such self-evident facts require explanation they assumed it is our cultural biases that prevent us from accepting such self-evident facts. Both attacking the same problem from two different directions.
ThomasT
#52
Feb2-12, 05:45 PM
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Thanks for recent feedback.

Info from these links helped a lot also:
Descartes Epistemology from the Stanford Encyclopedia of Philosophy
Cogito ergo sum from Wikipedia
Descartes Legacy from the Stanford Encyclopedia of Philosophy
Jimmy Snyder
#53
Feb5-12, 10:18 AM
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In the book, Discourse on Reason, by Rene Descartes, written in 1637, he says "I think, therefore I am". Of course, he was relying on the earlier work Discount on Raisins written by Jewish Dior in 1636 in which he wrote "That which thinks, is". When discussing this issue, you should mention both statements and you shouldn't put Descartes' before Dior's.
DaveC426913
#54
Feb5-12, 10:24 AM
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Jimmy, Jimmy, Jimmy...


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