https://www.umsu.de/trees/#((p~5q)~1p)~5q

That's the fully drawn out argument - not just the premise, the argument.

That means, arguments that take p implies q as a premise can be valid. It's not inherently invalid.

https://web.stanford.edu/~bobonich/terms.concepts/valid.sound.html#:~:text=Valid%3A%20an%20argument%20is%20valid,argument%20that%20is%20not%20valid.

Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false.
Invalid: an argument that is not valid. We can test for invalidity by assuming that all the premises are true and seeing whether it is still possible for the conclusion to be false. If this is possible, the argument is invalid.

Validity and invalidity apply only to arguments, not statements. For our purposes, it is just nonsense to call a statement valid or invalid. True and false apply only to statements, not arguments.

↪Banno So you really think all arguments that take p implies q as a premise are invalid? — flannel jesus

No. That is not what I said.

I can't distinguish between that and "p implies q is invalid". What are you saying if you're not saying that?

Here's the point: "I think, therefore I am" is not a valid argument if it is understood as p⊃q.

Even you must see that.

it isn't the argument. It's a premise. The full argument spelled out is here

https://www.umsu.de/trees/#((p~5q)~1p)~5q

Good. So you agree that, since for you it is not an argument, then it is not a valid argument.

Now, if it is not a valid argument, then it cannot be an inference.

So what is it?

How does it command 100% certainty?

If it is a premise, is your claim that it is just presumed?

I'm afraid what's happened is you've read Descartes flowery language and have taken it for granted that translating exactly what he said into symbolic logic is the right way to talk about the logic of his idea.

He's speaking poetically. He is writing succinctly, and with brevity, for aesthetics sake.

There are a few different ways of translating his poetic and flowery slogan into a syllogism. You haven't engaged with those.

Try to stay on topic.

What is the basis for claiming that "I think, therefore I am" is indubitable?

I don't have anything unique to say on the topic. To think, one must exist. It's pretty intuitive.

So the basis for 100% certainty in the Cogito is... your intuition?

Are you happy with that?

yeah, sure.

Do you think it's possible for you to think if you don't exist?

Do you think it's possible for you to think if you don't exist? — flannel jesus

Can you show me that it isn't?

Can you make the Cogito the result of an argument, rather than a mere presumption?

You are going to need something more than propositional logic.

I'm asking you what you think. I've asked you this before but you keep finding ways not to answer. What do you think? Do you think it's possible to think without existing?

I've answered that. Again, it is a loaded question.

If you are going to claim that the Cogito is 100% certain, then you presumably are able to set out why.

As it stands, it seems it is only because you are convinced by what you describe as "Descartes flowery language"...

I've answered that — Banno

I missed it. What's the answer? I don't think it's loaded, I think it's just completely pertinent. I've answered a number of questions from you, you won't answer one from me? I'm being honest and open about my thoughts, because quite frankly what's the point of being here if I'm not? I am open to having my mind changed, but only by someone open and honest about their thoughts.

Do you think it's possible to think without existing?

Do you think it's possible to think without existing? — flannel jesus

I do not think the Cogito convincing, on Tuesdays and Thursdays. Monday, and Wednesday, I'm quite convinced. Friday and Saturday, I take an agnostic position. Sundays, I rest.

Now, you think the Cogito is grounds for being 100% certain of your existence, on the basis of an intuition... is that right?

And do you Know, as a result of this intuition, that you exist? Is that a justified true belief? What justifies it?

That's not open and honest. That's just being silly.

You're allowed to say something like "I think you must exist to think, but I'm not 100% certain of that". You can put some caveats on your answer. It's okay. I just want you to be open and honest about it.

That was an honest answer: I don't know.

So help me - show me that "I think, therefore I am" is 100% certain.

With something more than your intuition.

That was an honest answer: I don't know. — Banno

That's not really what you said though, is it?. Anyway, I'll take the belated honest answer given here, you don't know. Wonderful.

I don't necessarily think there is more than intuition there. Maybe it is just intuition. It's an intuition that it seems most philosophers share, including even Corvus believe it or not.

Do you think I shouldn't be 100% sure because it's an intuition?

Me? I would have you to question the very notion of needing an absolute foundation for what you know.

I think you know plenty of things, like that I'm a bit of a twat, that this is a post on at best a second-rate forum, that you are reading this sentence - and all without the need for an absolutely firm foundation.

So to that end, I've been arguing that the Cogito is not as firm as folk otherwise suppose.

That'll do. We can leave Wittgenstein and Ordinary Language for another time.

I don't actually think you're a twat. Believe it or not, people disagreeing with me isn't inherently something that bothers me. I didn't fall out with corvus because he disagreed with me. If you're a bit of a twat, it's only because it took me so much effort to get you to answer a completely pertinent question - I like clarity and open honesty in these conversations. That really matters to me.

I don't know that I NEED an absolute foundation anyway. I don't agree with the cogito because I NEED to agree with the cogito. I agree with it because I read it and it resonates as truthful. Descartes ran a thought experiment where he doubted everything he could doubt, and then struggled to doubt two final things: he thinks, and he exists. He could doubt physical reality, he could doubt the existence of other minds, he could doubt the existence of gods or dogs or whatever, but if he doubted thought, the wall he hits is that that doubt is a thought...

I don't NEED to be 100% certain of cogito. I would be content being 99.99...% certain of cogito (or less, if there was a reason to be less).

Perhaps it's an intuition, but it's a unique intuition because there are multiple layers of reflexivity in it. It's a self referential intuition, because it's an intuition about the very things that allow you to have intuitions. It's a thought about thought itself. It's existence questioning it's own existence. It gives it a very different flavour from most other institutions. It feels that way to me.

What fascinating thoughts you have!

I think you are conflating the validity of formal logic with the validity of the cogito in particular.

One can maintain that cogito is valid.

Proving it is another matter.. if you don't get it you don't get it.

It indicates a process of thought not a proces of causation or chronology. The detective's thought process, not the scientists proclamation of causation and order in time.

So, again, I think you misunderstand 'therefore' and are confusing word order with a diagram of events in time. — Bylaw

I did bow out from this thread, but you have directed your post with your poorly reasoned writings to me, misleading my points. Hence I am briefly back for pointing out the problems in your post.

You totally distorted the meaning of the word "Therefore" in your claims. Therefore means  by the result of, for that reason, consequently.  Therefore it has implications of chronology and cause and effect transformation for the antecedent being the past, or cause, and the descendant to imply the result, consequence and effect.

If you deny that standard meaning, then you are denying the general principle of linguistic semantics.  And that is what you have done to mislead the argument and further present the nonsense.

Have a good think about these example sentences.

I drank, therefore I got tipsy.    You are claiming that Therefore has no implication of chronology or cause-effect consequence. Therefore you are claiming that  "you got tipsy therefore you drank." is the same meaning as the previous example. This is nonsense.

It rained therefore the ground got wet.  You are saying it is OK to say, The ground is wet, therefore it rained. No. They are not the same meaning, and the latter clearly doesn't make sense.

"Therefore" has the meaning of consequence, resulting from the antecedent.  Therefore, I think therefore I am saying that because you think, as a consequence you are, you exist.Your denial and distortion in that case by totally misleading the meaning of the word just sounded nonsense babble.

You are therefore you think just means that because you exist, you can think.  If you didn't exist, then you cannot think.  Nothing more to it apart from the logical illustration, your mental activities are only possible because you exist. Nothing wrong with that statement logically and ontologically, is it?

I have presented in my previous messages the formal logic how the Cogito is false, and if you examined the logical proof steps, you would know that it only makes sense because there are consequential, cause-effect links between the two events on both sides of Therefore.

So, do we agree that "p⊃q" is invalid? — Banno

The shape p→q is invalid under a broad definition of invalid, yes. Before you question me on what I mean by "broadly invalid", I will quote flannel quoting the SEP:

Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false.

A notion of validity seems to imply that there are premises and a conclusion, which p→q does not have. So under a broader notion of invalid (where validity does not even apply), p→q would be invalid, yes.

If yes, then do we agree that the Cogito is "I think, therefore I am"? — Banno

The translation of cogitō ergo sum is "I think therefore I am", nothing else.

If no, then what is the Cogito? — Banno

First-person singular of the present indicative tense of the verb cogitāre.
If you are asking what Descartes' argument is, I summarised it a few posts above a few times. For the actual argument, I can only recommend the books.

1. I think ⊃ I exist. (Cogito, assumption)
2. I think. (assumption)
3. ⊢ I exist. (1.2, MPP) — Banno

Descartes did not put his argument in syllogistic form, so there are a few ways you could translate it. Still, I will concede that is not Descartes' argument.

That as such, it would be circular? — Banno

If you are using ⊃ as material implication, is this https://www.umsu.de/trees/#(p~5q),p|=q circular? The problem for me is again that the first premise is unproven, not that it is circular.

And it seems we agree that the Cogito is — Banno

Descartes' argument itself is not an intuition, it is a full-fledged argument as I have shown and as can be verified in the books. It relies on intuitions, like any argument does. An intuition is a belief that is not proven by inference or by experiment. Descartes is not worried to try to prove everything, he uses hyperbolic doubt, not unbounded doubt, so he does not doubt things that could not be otherwise (something thinking but not existing, or 2+2=5).

Then, returning to the topic, do we have some basis for thinking that this intuition counts as part of the 100% certain knowledge that the OP seeks? — Banno

If the OP does not wish to doubt our basic intuitions of reason, which would undermine reason itself, Descartes' argument would count as something certain.
But then again, now OP seems to be sure even of things that he has no way of knowing for sure, such as the day of his birth.

Well put.

I swim, therefore I am wet.

If you define swimming as propulsion through water, then being wet is contained in, or comes along with, or is a consequence of, swimming.

So “therefore” here isnt pointing to a conclusion; it is pointing to a property or aspect of the premise. Swimming includes being wet. You say “swimming” you have already splashed some water on the statement.

I think therefore I am works like that.

I am isn’t a conclusion. It’s as much the premise as the conclusion. It’s just a premise that self-certifies it’s fact as a premise.

The cogito statement is an attempt to define self-certification.

All of the logical analysis is good, instructive of logic itself, pushing us all to clarify what we see here. But none of the logical analysis of the cogito syllogism really addresses the content of what Descartes was observing.

No matter how meaningless or meaningful we make the statement “I think therefore I am”, it would be more on point to talk about “making meaning” then whatever meaning is made.

“I am making the cogito look meaningless, therefore I am.” “Making” is the point. Something being always remains here and that is what Descartes said was certain about.

I am isn’t a conclusion. It’s as much the premise as the conclusion. It’s just a premise that self-certifies it’s fact as a premise. — Fire Ologist

In a proposition, it is. You are trying best to make the point. I can see that. But we are talking within the syntactic and semantic realm with no additives. If you beg for the possible assumptions and allowances into all the expressions, then there would be other folks keep coming back with some other possible assumptions in the expressions and sentences under analysis. It shouldn't be allowed.

Therefore it has implications of chronology and cause and effect transformation for the antecedent being the past, or cause, and the descendant to imply the result, consequence and effect.

If you deny that standard meaning, then you are denying the general principle of linguistic semantics.  And that is what you have done to mislead the argument and further present the nonsense. — Corvus

I'm pleased that this is being spelled out explicitly. I can assure you, most people on this forum don't share your view on this, most philosophers in general don't, most logicians don't. "Therefore" doesn't have the chronological relationship you think it has - it CAN flow in that direction, but the chronology can flow in the other direction as well.

https://www.csus.edu/indiv/m/mcvickerb/problem_solving/logic/simple_logic_form.htm#:~:text=The%20first%20example&text=All%20rainy%20days%20(A)%20are,a%20cloudy%20day%20(B).

The two top examples on this page from California State University show a reversed chronology, where A therefore B involves a B that happened before A. (The second example might be debatable, the first less so)

Bylaw is not denying basic language or logic, you are.

I swim, therefore I am wet.

If you define swimming as propulsion through water, then being wet is contained in, or comes along with, or is a consequence of, swimming. — Fire Ologist

"I am wet, therefore I swim." doesn't make sense, as "I think, therefore I am." doesn't make sense.
"Think" doesn't warrant for anything. "Think" means "think".