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I think therefore i am is often accepted as true.But how do we know that the fact we are doubting something makes us real?we can be a stimulation or be dreaming.Why is the act of thinking given so much importance when it actually does not tell us any reality?

marked as duplicate by virmaior, Swami Vishwananda, Nick R, Conifold, Heinrich Sep 20 '17 at 14:39

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    If your question is distinct please make the distinction clearer. We get a question on the cogito every week or so... – virmaior Sep 12 '17 at 5:27
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    The fact that I am doubting implies (according to D) that there is an "I" performing the act of doubting. – Mauro ALLEGRANZA Sep 12 '17 at 6:40
  • The point is even if I am a dream or a simulation, I'm still something! – infatuated Sep 12 '17 at 7:38
  • 'I am' cannot be falsely stated. 'I think' is a can of worms. But 'I think; is redundant to his case and is often criticised for being dubious or unclear. . . – PeterJ Sep 12 '17 at 9:17
  • Cogito is where reflection begins (for there exists pre-reflective consciousness, too). Cogito is thus split into the thought itself (about its subject) and the awareness that the thought "is being considered" while it thinks. Therefore the thought appears to itself an object being posed, posed from aside or by "somebody". That is enough for the sense of being fixed here, or "I am", to rise. – ttnphns Sep 13 '17 at 4:29

we can be a stimulation or be dreaming.

Descates is trying to prove that we are not in a simulation or dream. He cannot prove it using observation or the senses, since any simulation or dream would mean that what we observe or what we sense is fake. That's the whole point of simulations, dreams and hallucinations: We cannot trust the senses.

So instead he tries to prove it using reason and logic alone. That is, he is using a rationalist Approach to prove a fact without having to resort to empirical data.

Here's another way of putting it: The skeptic says: "It is possible that everything is an illusion" Descartes responds: "I will show how that is not possible by proving the existence of something without referring to any sense data or observations, using reason alone."

But how do we know that the fact we are doubting something makes us real?

Descartes uses the following approach:

  • I can doubt the existence of my body, I can never be certain that my body exists.
  • I can however be certain that "doubt" is real, since the very act of doubting means that "doubt" happens.
  • So we are now certain of the existence of doubt - but doubt is a type of thinking, so being certain of the existence of doubt means also that I am certain that I think.
  • So even though it is possible that my body is an illusion, a trick, a dream, or a simulation, it is not possible in the case of my mind. I am certain that I am thinking and therefor I am certain that my mind is real - cogito, ergo sum - I think, therefore I am.

Why is the act of thinking given so much importance when it actually does not tell us any reality?

This is one of the main objections to Descartes reasoning: He says that thinking proves the reality of "I", that the mind is real and independent of the body. Several authors point out that all he proved is that "thinking" is real - but there's no reason why the reality of thinking implies the reality of "I", the thinking can be real, but the "I" can still be an illusion. See this response for more details.

  • "thinking" is an ill-defined term of folk psychology, and Descartes certainly didn't prove anything about it, including that it "is real". To view "doubting" as a form of "thinking" is just more circularity. The language of folk psychology does not map directly to brain processes. – Jim Balter Apr 13 '18 at 22:26
  • ad hominem, "hardline" is pejorative, and "eliminativist" alone is meaningless; one is eliminativist in regard to some specific thing. Nothing I wrote is actually eliminativist, or even controversial ... if you "haven't [?] one" like me recently then you're not getting out much. I won't respond further. – Jim Balter Apr 14 '18 at 1:41

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