Not worth more discussion to me considering I find the "Cogito" vacuous. Cop-out? Not intentionally. But it's easy for you to find out for yourself, frank, how the philosophers I mentioned (& others) have either objected explicitly to the "Cogito" or implicitly rejected it by profferring alternative existential "grounds" for philosophy, science, art, religion, etc.

It's vacuousness interested you enough to comment 8 or 9 times in this thread, and when asked for a few sentences on how a parade of philosophers ”laughed it out of court”, your interest falls off. Uh huh.

But thanks for the encouragement to learn something about philosophy. That's a great idea.

The difference between making arguments of my own and tediously digging up arguments from philosophical history for someone else should be obvious. Besides, I wouldn't want to deprive you of the pleasure of self-discovery: 'Cartesian doubts' (i.e. Peirce called them "paper doubts") have been passé among (most non-idealist) philosophers for centuries.

As I said, I know what Hume said. I know the cogito wouldn't have bothered Schopenhauer, in fact it would have helped him make his point.

So if you're wrong about those two, I figure you're probably wrong about the rest.

Have a good evening.

Okay then. You have a good one too.

"Ergo, if I = something that's thinking, you are me, I'm you, you're Descartes, Descartes is me, so and so forth until I = everyone."

I don't agree with that. "I" /= "something that's thinking". "Something that's thinking" is a necessary condition for the self to exist, but it's not a sufficient condition. I like the definition of the self as "this particular conscious awareness". — RogueAI

We're on the same page.

Are there sufficient grounds to doubt that everything exists?

If yes, then state what such grounds might be.

If no, then it doesn't matter whether or not one can "doubt doubting" because one cannot doubt without grounds, and therefore, by default, one must believe whatever one cannot doubt exists exists.

Doubting, therefore doubting happens.

:roll:

With respect to Kant at least, there’s no philosophical laughing, but there is a basic refutation.....

“...The "I think" is, as has been already stated, an empirical proposition, and contains the proposition, "I exist." But I cannot say, "Everything, which thinks, exists"; for in this case the property of thought would constitute all beings necessarily. Hence my existence cannot be considered as an inference from the proposition, "I think," as Descartes maintained—because....”

....and I say basic because it occurs in a mere footnote to B422, and I say refutation, as shown by the “ -because...”, insofar it is only so in accordance with Kant’s philosophy, which employs a conceptual scheme Descartes didn’t, re: the categories.

On the other hand, Kant congratulates Descartes for not making the same absurd claims with his idealism in general, as Berkeley made with his, so.....it’s a wash. Praise on one hand, criticism on the other.

“...The "I think" is, as has been already stated, an empirical proposition, and contains the proposition, "I exist." But I cannot say, "Everything, which thinks, exists"; for in this case the property of thought would constitute all beings necessarily. Hence my existence cannot be considered as an inference from the proposition, "I think," as Descartes maintained—because....” — Mww

Why would Descartes need "Everything, which thinks, exists" to be true in order to infer his own existence from the fact that he's thinking?

Why would Descartes need "Everything, which thinks, exists" to be true in order to infer his own existence from the fact that he's thinking? — frank

Ahhhhh....the subtleties of philosophical investigations.

What do you think “infer his own existence” to mean?

What do you think “infer his own existence” to mean? — Mww

Up to this point he's been wondering if he could be tricked into a false belief. Now he asks if his belief in his own existence could be wrong. Is he being tricked again?

He realizes that he can't be wrong because he's aware of his own thoughts.

Is the complaint that he hasn't executed a proper ontological proof?

Thanks for being open to subtlety.

Is the complaint that he hasn't executed a proper ontological proof? — frank

I don’t think Descartes meant to infer his own existence, with the predicate “...therefore I am”.

I don’t think Descartes needed an ontological proof for anything, insofar as his sole intent was to prove a distinction between mind and body. The method for proving a distinction does not need an ontological proof for its elements, as much as it needs validation of an absolute necessity of one of them. All he had to do was show how the doubting one set of conditions for a thing, was impossible for doubting some other set of conditions for some other thing. It follows that if doubt of that other thing is impossible, that other thing must be absolutely necessary. He then has no need to prove the existence of it, having already proven its necessity. So it is, that because “I think” is undoubtably, “I am” is given necessarily.

Another way to look at it is, logical consistency reduces the “I” that thinks, to be the very same “I” that is thinking. “I” think, therefore “I” am. As such, “I” isn’t proven to exist, only that it is simply proven, by its thinking.

I think Descartes’ mistake was not to eliminate the extension of “I am” to phenomenal existence. So in effect, I guess you could say he failed to provide an ontological proof for the impossibility of mind as such. And he failed at that, because, as aforementioned, he didn’t consider, or at least didn’t use, the categories, as did Kant, it being reasonable to assume he knew about them, at least in Aristotle-ian form.

As an aside, there is also a standing Kantian metaphysical argument, unknown and/or not recognized as valid by Descartes, that existence cannot be a predicate in a logical proposition. So, if “I think” is true, “I am” is given immediately because of it. I mean....how could it be that “I think” but “I am not”.

Subtleties indeed. As in Tonini, I’ll wager.

And he failed at that, because, as aforementioned, he didn’t consider, or at least didn’t use, the categories, as did Kant, — Mww

Could you explain how his outcome would have been different if he had?

As an aside, there is also a standing Kantian metaphysical argument, unknown and/or not recognized as valid by Descartes, that existence cannot be a predicate in a logical proposition. So, if “I think” is true, “I am” is given immediately because of it. I mean....how could it be that “I think” but “I am not”. — Mww

He believed a thing's essence can be examined without knowing whether a thing exists, except for God, which apparently exists by definition.

So maybe the meaning of the cogito is obscured by the change from medieval to modern ideas about existence?

Subtleties indeed. As in Tonini, I’ll wager. — Mww

I get the impression IITs proponents think of it as a first step.

The statement in question is from "Discourse on The Method of Rightly Conducting One’s Reason and Seeking Truth in the Sciences".

In Part 1 he says:

From my childhood they fed me books, and because people convinced me that these could give me clear and certain knowledge of everything useful in life, I was extremely eager to learn them. But no sooner had I completed the whole course of study that normally takes one straight into the
ranks of the ‘learned’ than I completely changed my mind about what this education could do for me·. For I found myself tangled in so many doubts and errors that I came to think that my attempts to become educated had done me no good except to give me a steadily widening view of my
ignorance!

Descartes first stated intention is to break with the past. To begin again without reliance on what others have said.

Part 4 begins:

I don’t know whether I should tell you of the first meditations that I had there, for they are perhaps too metaphysical [here= ‘abstract’] and uncommon for everyone’s taste. But I have to report on them if you are to judge whether the foundations I have chosen are firm enough. I had long been aware that in practical life one sometimes has to act on opinions that one knows to be quite uncertain just as if they were unquestionably •true (I remarked on this above). But now that I wanted to devote myself solely to the search for truth, I thought I needed to do the exact opposite—to reject as if it were absolutely •false everything regarding which I could imagine the least doubt, so as to see whether this left me with anything entirely indubitable to believe.

'I' occurs 10 times in this paragraph, 'myself' and 'me' occur once each.

He begins anew with himself.

I decided to pretend that everything that had ever entered my mind was no more true than the illusions of my dreams ...

Emphasis added.

But no sooner had I embarked on this project than I noticed that while I was trying in this way to think everything to be false it had to be the case that I, who was thinking this, was something.

Emphasis added.

He only pretends to doubt because as a practical matter one cannot doubt everything. In matters of knowledge or science Descartes replaces the doubted authority of the "learned" with "I" or one who uses the method of rightly conducting one’s reason.

Could you explain how his outcome would have been different if he had? — frank

No, not with any legitimacy. I can philosophize all day long over it, but that would never be any more than making inferences based on my understandings, which are most likely not even be close to his. He had a different mindset and different authorities to answer to than I, after all.

The statement in question...... — Fooloso4

I like the “Principles of Philosophy” exposition more. Simpler, with a follow up for what he means by “think”.

From the Meditations:

Well, then, what am I? A thing that thinks. What is that? A thing that doubts, understands, affirms, denies, wants, refuses, and also imagines and senses. (Second Meditation)

One thing I find odd about the Principles is that he says it is not necessary to define terms (10) but he says this right after defining thought (9). It may just be a response to critics who did exactly what some here are doing.

:up: It's all pretense. And yet so many are ... misguided.

Is it the same to define a term, as it is to declare how it is meant to be understood? Descartes tells us what he means by the use of a term, e.g., P.P 1,9, on “thought”, insofar as when he is thinking all these listed mental occurrences are predicates of it, but he didn’t really define it, per se, as did Kant with his “thought is cognition by means of conceptions”.

As well, in P.P. 1,10, he warns against over-complicating “items of knowledge”. Then it is the case that “logical definitions for very simple and self-evident matters” should be unnecessary, because these should be taken as the very principles upon which the treatise is grounded.

Still, I would agree P.P. may very well be a response to critics, in which he is clarifying his intended use of terms, or, “items of knowledge”, rather than setting definitions of them.

What did you have in mind with “exactly what some are doing here”?

Is it the same to define a term, as it is to declare how it is meant to be understood? — Mww

I think there is some truth to this, but first an objection. How a term is meant to be understood is by definition a definition. He does make a distinction though:

But these are utterly simple notions, which don’t on their own give us knowledge of anything that exists ...

I take his point to be that we do not gain knowledge by analysis of definitions. It is in this regard a rejection of the method of Euclid.

But how he uses the term 'thought' is not "self-evident" or "sufficiently self-explanatory". His use of the term 'thought' includes sensory awareness. Can the mind/body distinction be made if sensory awareness is a matter of thought? He elsewhere claims the "substantial union" of mind and body. This is problematic because he identifies himself as mind or soul, in which case the body is other than one's self. The union then would a union of self and other.

How a term is meant to be understood is by definition a definition. — Fooloso4

Objection noted, and agreeable in principle. A definition is the complete representation of the conception, which always arises spontaneously from the understanding alone. How I define a term is represented by how it is understood by me.

Problem is, of course, there is no promise of necessary congruency between a plurality of understandings, from which follows the possible disparity between definitions, i.e., complete representation, of the same conception. I rather think how a term is meant to be understood, is the explanation of it, integral with its propositional employment.

Minor point, far deeper into the weeds than necessary.
—————

we do not gain knowledge by analysis of definitions. — Fooloso4

Correct; knowledge is far more complicated than that.
—————

Can the mind/body distinction be made if sensory awareness is a matter of thought? — Fooloso4

How about......awareness of, e.g., pain, is an indubitable certainty, a product of mind, even if its cause is not, it being a product of body. Difference between aware of, and aware-ness of. I suppose there’s all kinds of ways to distinguish one from another, right?

I wanted to follow up on my comment about Euclid. Cartesian coordinates lined Euclidean geometry and algebra. Descartes sees it as a method for solving for any unknown. Symbols replace things.

I suppose there’s all kinds of ways to distinguish one from another, right? — Mww

One question that occured to me but I did not pursue it before is, why does he want to distinguish them?

why does he want to distinguish them? — Fooloso4

In modern parlance.....the quest for the unconditioned? The irreducible. The absolute certainty. From which the possibility of knowledge itself is given.

Recognition of the validity of thinking outside the Bible.

Some thoughts:

Descartes also did work in natural philosophy, optics, mechanics, physics, medicine, and so on. By regarding the physical world as mechanistic he jettisons final causes as well as the idea that mind or reason or God guides the course of things.

Recognition of the validity of thinking outside the Bible. — Mww

Descartes, like all educated people of his age, knew the Bible. I think he used the Bible to do something that was at once consistent with it and contrary to it.

Descartes also did work in natural philosophy, optics, mechanics, physics, medicine, and so on. By regarding the physical world as mechanistic he jettisons final causes as well as the idea that mind or reason or God guides the course of things. — Fooloso4

Aquinas advocated a mechanistic approach to the world, and final cause has yet to be jettisoned from science because it's embedded in biology.

There is no clear point at which the churches, Protestant and Catholic ceased to be Europe's champions of education and science. It happened slowly.

Aquinas' physics is Aristotelian. It includes formal and final causes. In addition, his use of the term substance is different from Descartes. For Aquinas a substance is a thing. He uses the example of Socrates as a substance. For Descartes substances are not particulars, there are two substances, thinking and extended.

Yes. Socrates is an Aristotelian substance because he isn't a dependent entity. That doesn't conflict with my point.

I don't think particulars as substances is compatible with Descartes' mechanistic view. Descartes does not deal with such things as prime matter and substantial change.

final cause has yet to be jettisoned from science because it's embedded in biology. — frank

Are you claiming that final causes are embedded in Descartes' biology? He does, after all, regard animal bodies as machines, automata.

But perhaps I have missed your point.

I’m aware of but not well-versed in Descartes’ science, having more interest in his metaphysics. I shall have to take your word for it, that he regards the world as deterministic, so jettisons final causes. But if he claims that mind, body and god all are not responsible for guidance in the course of things, does he then claim Nature itself, is? I mean....what’s left? That, or the course of things isn’t guided at all, I guess. Excluded middle kinda thing.
—————

at once consistent with it and contrary to it. — Fooloso4

Yeah...if you’re gonna upset the applecart, ya gotta be ready to appease the owner.

But if he rejects that mind, body and god all are not responsible for guidance in the course of things, does he then claim Nature itself, is? I mean....what’s left? That, or the course of things isn’t guided at all, I guess — Mww

A mechanical system, a clockwork for example, does not need guidance. It is all just a matter of the shape of extended things in motion.