Descartes: I Think Therefore I Am

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In summary: But, at the very least, the idea of "I think therefore I am" is a strong statement that can be backed up with evidence.In summary, Descartes' "I think therefore I am" phrase is a strong argument that can be backed up with evidence.
  • #36


ThomasT said:
I think that I take that ... by definition/convention. There's no faith involved there as far as I can tell.


That definition rests on assumptions that Decartes wasn't willing to make(for his argument). So yes, there is some faith involved from his POV.


That's not unsatisfactory. It's convention. It's a function of our apprehension and recording of what we call reality, and the way we communicate that.


That would not be rigorous proof by the standards Decartes set.


Descartes said, "I think, therefore I am". It's a tautology. The "I am" is implied by the "I think". Descartes might just as well have said, "I am". Whereby, the "am" is implied by the "I".


Not according to latest neuroscience. "I think" carries much less weight(and appears to come after the fact) than "causal deterministic processes determine the brain's thoughts". If one's thoughts are predetermined and resultant from processes over which 'you' have no control, would it make sense to say that the "I am" is implied by the "I think"?
 
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  • #37


wuliheron said:
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.
 
  • #38


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

ThomasT said:
"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.

ThomasT said:
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?
 
  • #39


DaveC426913 said:
So, if I define myself as stinking rich, I am?
I stink. Therefor I am rich.
 
  • #40


Jimmy Snyder said:
I stink. Therefor I am rich.

I thought you were Jimmy?
 
  • #41


DaveC426913 said:
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.)

DaveC426913 said:
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.

DaveC426913 said:
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.
 
  • #42


DaveC426913 said:
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.
 
  • #43


"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.
 
  • #44


Char. Limit said:
"I think therefore I am" is definitely NOT a tautology.
Yes, I see that now.

Char. Limit said:
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.
 
  • #45


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.
 
  • #46


Char. Limit said:
Well of course "I cook therefore I am" is a valid statement.
That's what I thought.

Char. Limit said:
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?

Char. Limit said:
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"?
 
  • #47


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.
 
  • #48


ThomasT said:
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.
 
  • #49


ThomasT said:
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.
 
  • #50


ThomasT said:
...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. :smile:

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.
 
  • #51


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.
 
  • #53


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.
 
  • #54


:smile: Jimmy, Jimmy, Jimmy...
 
  • #55


"I think, therefor I am... a thinker. Derp"-anonymous
 
  • #56


Jimmy Snyder said:
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.
I was wondering when somebody would come up with the obvious humorous take on this. Nicely done.
 
  • #57


OP, first it should be noted that in the form you set out his argument to be it would, strictly speaking, not be a circular argument. Saying that "P is true. Q is true. Therefore P is true" is not "circular", it is, on the other hand, tautologous. It is of the form
((P&Q)->(P)) which is always true. This is not what Descartes was saying, nor how he argued it. What he was saying was that in order for there to be any thinking or experiencing in general, there must some thing that is doing the thinking, acting or what have you. He said that existing is a necessary condition for thinking, so he would actually be arguing more closely to modus ponens: (P&(P->Q)->Q). "I know that I think, and thinking implies being, therefore, I must exist". His argument most certainly could not be "I am therefore I think" for then you would be saying "For any object, if that object exists, then that object thinks" and in order to disprove that all I have to do is say the contrary "There exists at least one object which is and does not think" and this, of course, is quite easy to show: Look around you. (Not to mention if you admit platonic entities like triangles, surely they do not "think").

The problem with your "unicorn" example is one of modality. That is to say "being pink" is only a contingent property of a unicorn (haha). Descartes argued that necessarily being precludes thinking, wheras being pink is certainly not a necessary condition for being a unicorn. Unless you are assuming that it is, but even then you would have to say "All Unicorns are Pink. Unicorns exist. Therefore there are pink unicorns". Also, also unicorns could very well be pink even if they don't exist. Depending on what you mean by exist, but then we get into some sticyk situations. (Remember the King of France? That bald guy?). I could say "How could Luke Skywalker be from Tatooine when both don't exist?", but it depends on what we mean by exists and how we judge the truth conditions of a proposition like that.

As for "I think" being able to be replaced by anything. Maybe. You could say you are deceived about everything, but thinking is a precondition for anything and is thus more fundamental, but that may just be a Western bias. The idea that "mind" is more pure and more fundamental and that we are thinking beings above all else is not necessary to the argument. You could say, most generally, I experience, therefore I am. For to experience anything must imply some form of existence even if the experience itself is an illusion.

Yes, it may be difficult to prove existence through words alone. "Don't mistake the finger for the moon". This is why, as someone pointed out, (well notneccessarily why) asian cultures focus on cultivating a type of "orginal experience" of the world, a non-judgemental form of being, through practices such as yoga and mediation and what not.

Oh and Philosophy is certainly not a part of linguistics. Linguistics is the study of language; its syntax,semantics, etc etc and justl ike any good science it found its roots growing out of philosophy.
 

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