Does Descartes' "I Think Therefore I am" really prove anything?

Question

"Cogito, ergo sum"—I think therefore I am...Descartes believed that he could not trust his senses to portray reality, but rather he could only use his mind, and ideas which stemmed from the mind (like math) to prove reality...does the logic behind this really hold up? Does anyone have any ideas as to how to disprove this famous theorem?

just some food for thought...

Answer 1

Descartes was right, the only thing you can prove is, I think therefore I am. Or as a friend of mine liked to take it one step further, "No, you think therefore you have thought". The truth of the matter is we are subjective beings. We cannot say for sure whether or not we are dreaming, hallucinating, or are a brain in a vat being stimulated by a mad scientist. Now, there is no need to throw yourself off a bridge in existential angst. From the starting point of realizing our subjective natures we can begin to make reasonable assumptions based off our senses, experience, and logic/intuition. But that's a whole nother story.

Answer 2

"Descartes is sitting in a bar, having a drink. The bartender asks him if he would like another. "I think not," he says, and vanishes in a puff of logic. "

"Common errors
Some non-philosophers who first come across the cogito attempt to refute it in the following way. "I think, therefore I exist," they argue, can be reversed as "I do not think, therefore I do not exist." They argue that a rock does not think, but it still exists, which disproves Descartes' argument. However, this is the logical fallacy of denying the antecedent. The correct corollary by modus tollens is "I do not exist, therefore I do not think."

. . . .

Criticisms of the cogito
There have been a number of criticisms of the cogito. The first of the two under scrutiny here concerns the nature of the step from "I am thinking" to "I exist". The contention is that this is a syllogistic inference, for it appears to require the extra premise: "Whatever has the property of thinking, exists", and that extra premise must surely have been rejected at an earlier stage of the doubt.

It could be argued that "Whatever has the property of thinking, exists" is self-evident, and thus not subject to the method of doubt. This is because it is true that any premise of the form: "Whatever has the property F, exists", but within the method of doubt, only the property of thinking is indubitably a property of the meditator. Descartes does not make use of this defence, however; as we have already seen, he responds to the criticism by conceding that there would indeed be an extra premise needed, but denying that the cogito is a syllogism.

Perhaps a more relevant contention is whether the 'I' to which Descartes refers is justified. In Descartes, The Project of Pure Enquiry Bernard Williams provides a history and full evaluation of this issue. The main objection, as presented by Georg Lichtenberg, is that rather than supposing an entity that is thinking, Descartes should have said: "thinking is occurring." That is, whatever the force of the cogito, Descartes draws too much from it; the existence of a thinking thing, the reference of the "I", is more than the cogito can justify.

Williams provides a meticulous and exhaustive examination of this objection. He argues, first, that it is impossible to make sense of "there is thinking" without relativising it to something. It seems at first as though this something needn't be a thinker, the "I", but Williams goes through each of the possibilities, demonstrating that none of them can do the job. He concludes that Descartes is justified in his formulation (though possibly without realising why that was so).


Williams's argument
Whilst the preceding two arguments against the cogito fail, other arguments have been advanced by Williams. He claims, for example, that what we are dealing with when we talk of thought, or when we say "I am thinking", is something conceivable from a third-person perspective; namely objective "thought-events" in the former case, and an objective thinker in the latter. The obvious problem is that, through introspection, or our experience of consciousness, we have no way of moving to conclude the existence of any third-personal fact, verification of which would require a thought necessarily impossible, being, as Descartes is, bound to the evidence of his own consciousness alone."

Answer 3

The question is still open. How do you isolate the mind from the senses? Isn't what we call "thought" served on a platter constructed from what our senses have told us of our environment? And if you begin to remove differrent parts of our senses what happens to our mind at a conscious intellectual level? Can a blind person understand what is color? At a certain atomic level color IS math or at least that is a way to describe it. Can a person raised in a state of isolation from "normal" life ever reach the level of understanding that allows them to state questions like Descartes?

I find it interesting that religions and philosophies that attempt to protray some higher level of being almost always criticize the real world as being crude and limited. And yet, the same people who promote these ideas could have never reached their socalled "understanding" without having spent time in the very world they now deny.

Answer 4

If you are speaking of the physical world the logic is fine. However ,we do not exist only on the physical plane. Can't see a thought can you? I believe we exist on many dimensions,the physical,being the most temporary.That is why so many have trouble with God,{they try to explain or understand him using physical terms or references} Whereas he exists in a dimension that we can't imagine because we have no reference points.However if He came to us in a body of a man perhaps we would understand just enough to know this; " So if we think,we exist."The question is not really "are we" but "why and how".It has taken mankind hundreds of years to come to the reasoning of 11 dimensions of existence,although I'm not sure they have considered number 11 yet. Who would ever thought that ,"how small is small,and how large is large would have the same answer?

Answer 5

within the framework of Western philosophy, this is a real chestnut and represented a return to logic after years of ignorance. When viewed from an Eastern philosophy, like Yoga, it could be seen as silliness, Maya's illusion, and not needing refutation.

Answer 6

The Roman orator Cicero once warned his audience that they were in danger of making philosophy a substitute for action instead of allowing it to produce action. You can sit around and analyze all day long, but do you really get anywhere?

Answer 7

All living things are made up of positive energy which is "alive"... the universe, air, oceans, rocks etc etc etc and they all have specific processes involved with their own particular cycles of life. To "think" is relative, simply not understanding the manner in which something else other than human beings may "think" does not mean that it doesn't, all life "IS", therfore it can be applied to all life as we perceive it as well as ourselves.

Answer 8

I guess Descartes is right about his proof of human existence.
I reckon we define our existence as a truth. All basic concepts as love, life, length, time are not definable.

Answer 9

yes it does, but because you miss understood the meaning: Cogito, ergo homo sum, it is more appropriate. he underlines the fact that we are conscious of our existence. check out Bergson and his cane

Answer 10

Nope-nothing proves anything.
Therefore, nothing to disprove