What is Thought? Rene Descartes' Existential Proof

[kurt.physics]

My Question is, What is thought and how did Rene Descartes come to conclusion that thought proves our existence; "I think, therefore, I am"

 

[JoeDawg]

Descartes was looking for a bullet proof argument against radical skepticism.

If I say the chair I am sitting on exists, a radical skeptic can ask, how do you know you are not dreaming the chair?

So Descartes went to great lengths to strip away all the things that he couldn't be 'certain' of. What he found was that even as a radical skeptic, he could be certain that he was being skeptical... or doubting the chair. The act of doubting the chair is thinking. So Descartes came to the conclusion that since he could doubt, he was thinking, and the process of thinking implies that 'something that thinks' exists. So, Cogito Ergo Sum, "I think, therefore I am"... something that thinks.

 

[out of whack]

"Cogito ergo sum" is paraphrased as "thinking requires existence". I have seen posters who disagree that existence and/or change are undeniable, but these objections usually involve unusual or uncommon definitions of one of these three words. Here are my definitions followed by their justification.

1. To think: to change state of consciousness.
2. To require: to imply.
3. To exist: to matter, to have significance.

1. We are conscious of many different things, either through our perceptions or within our own mind. We also observe within our own mind that everything we know, reason or remember does not occupy us all at once but a few thoughts at a time. Mental concepts arise in succession: thinking happens because our state of consciousness is not frozen in a constant state. The self-evident observation that we change state of consciousness defines thinking. Thinking itself is inescapable: not only do we witness it directly but even denying it would be a change of consciousness from not denying (or not even considering it) to denying it; this change of consciousness is thinking, as defined here.

2. To "require" means to imply in the logical sense. Saying that A requires B is the same as saying that B is necessary to A, or that if B is false then A is also false, or that A implies B.

3. To exist means to be significant is some way, it means to matter to anyone or to anything, anywhere at any time under any condition. If it matters, it exists. If it does not exist then it does not matter. The equivalence of "what exists" and "what matters" is underlined by two observations based on the following tautology: we are concerned with what matters and what matters concerns us. First, it would be meaningless to say that something matters but is said not to exist because this case would be indistinguishable to our concerns from something that matters and actually exists. Second, it is also meaningless to say that something does not matter but is said to exist because this case is indistinguishable from something that does not matter and does not actually exist. The equivalence is natural as long as we are concerned with what matters and unconcerned with what doesn't (any other stance being useless for all purposes).

So thinking happens and thinking requires change. Change matters at least to our own self. Consequently, our consciousness matters and so it exists. Change and existence cannot be denied.

You may object to the definitions if you consider that they are flawed or are not useful. You can object to the logic as well, but I think that's harder to do for these particular interpretations of the words.

 

[Ki Man]

I can't think of an a...