Do you believe you can jump from "p implies q" to "not p implies not q" in general? — flannel jesus
I think what he is trying to show here is that we cannot successfully use logic on the cogito in a way that it makes sense. From this, we can conclude that there is something wrong with the cogito. For example, it would obviously make no sense to say, "I do not exist, therefore I am not thinking" because you cannot be thinking about not thinking unless you exist. Or, you cannot say 'I do not exist' if you do not exist. Now, you may reply, "Oh, that was Descartes's exact point: if you are thinking, then you must exist." However, since 'I do not exist, therefore I am not thinking" DOES NOT make sense, then logically, the cogito also does not make sense. As has been pointed out many times, the 'I' is not logical here. To make it logical at a stretch (whilst having to make assumptions) we would have to change it to: 'He thinks therefore he exists.' Then, we can more logically say: 'He does not exist, therefore he is not thinking.' But, as I am sure we are all aware, the cogito ONLY works from the first person perspective. Therefore, it fails; it all fails — Beverley
Does this make sense? I am just checking. Please do point out if I have made a mistake somewhere. — Beverley
He based his logic on the premise that you can jump from "p implies q" to "not p implies not q" in general. You can see him present the argument here. — flannel jesus
Moreover, it is a circular statement. How the hell does he know that he exists? He was supposed to doubt everything. — Corvus
This is why the logic is not working. You cannot doubt everything and then suddenly, magically be certain of something. That is not too hard to understand, in my view. It is impossible to beat the skeptics at their own game. The only way to 'beat' them is to NOT PLAY THE GAME. — Beverley
Therefore if P-> Q, then Not P -> Not Q must hold. — Corvus
Therefore if P-> Q, then Not P -> Not Q must hold. — Corvus
So would you mind trying to establish with me if its generally true to say "if P-> Q, then Not P -> Not Q must hold."? I would love to have this basic logic established, as it has so far been a fundamental part of Corvus reasoning to this point. — flannel jesus
You are back! Yay! You are not collapsed in an exhausted heap trying to explain over and over why the cogito is not valid ... since page 14! Considering we are now on page 28, I'd say you have a whole lot of stamina! — Beverley
So would you mind trying to establish with me if its generally true to say "if P-> Q, then Not P -> Not Q must hold."? I would love to have this basic logic established, as it has so far been a fundamental part of Corvus reasoning to this point. — flannel jesus
Yes, I am bowing out from this thread after this message. I was going to do that about 10 pages ago. But I was getting frustrated to see the continuing confusions and groundless claims. It seems it better not to waste any more time, if the confusions going to continue, then let them get on with it. I don't see their views ever changing with no matter what rational explanations were given judging by their continuous circulatory posts.
Will get on with some other topics and readings. Thanks for your input on the point. :pray: :up: — Corvus
Hold on, I should have added, IF you are playing by the rules of logic, and the original premise was valid and logical, then, if what I have read is correct, the 'not P, not Q' reasoning would not hold. — Beverley
I do not blame you at all. I would have bowed out much sooner! You lasted for pages without agreement from anyone but didn't give in. I am really impressed! — Beverley
This is exactly what the cogito is asserting.Existence comes first. Logically, and ontologically. — Corvus
If you do what you suggest here, you are actually arguing in favor of panpsychism. That which exists can then think.Then he should have said, "I exist, therefore I think." He obviously misunderstood something.
He put the cart in front of a horse.
Sum, ergo cogito, makes sense. But it doesn't say anything new or exciting, does it?
You support the cogito.Existence comes first. Logically, and ontologically
Russell is saying that Descartes does not prove that thoughts need a thinker. — Beverley
You assume your conclusion in the first line of your argument. — Banno
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