I think therefore i am.....

Great Debates
161

Roughly, ontology is the study of being or existence, while epistemology is the study of the nature of knowledge, and its acquisition. Descartes is primarily concerned with epistemology: what we can doubt we know and what we can know for certain without doubt. What we end up knowing for certain in his case is ontological: that the doubter in question exists.

The border between epistemology and other studies is not always clear, but a useful rule of thumb would be whether we are probing into the nature of what we know rather than the content it is an epistemological question. So all questions of certainty are epistemological. What we are certain of is a broader question, and in this case is ontological. Such a distinction is not always necessary to make, but I think it is in this case.

I am saying he said “I am” in order to conclude that “I think” in order to conclude “I think therefore I am”, whether he thinks so or not.

Yes he was proving he existed to himself which, I’m sorry to say, is circular. It is a clever circle the way it is constructed, but it is circular nonetheless. :slight_smile:

I don’t recall mentioning whether or not he discussed a physical body at all until it was brought to my attention, and I only made a remark on it in the quote of his exposition. It was never in my mind to wonder about whether we could distinguish different types of existence, and if we could, whether we were concerned with all of them or not. I think his argument is clear enough. Honestly.

I brought it up because it is important to his argument to discount physical existence as necessary. He was a dualist. That’s the kind of thing that dualists like. It was germaine because he mentioned it, and my comment was not supposed to be a critique of his position but a note to the reader that this particular question is not one we are concerned with. I had hoped that would avoid whatever hijack/trainwreck this has become. :wink:

Accusations of idiocy? If I wanted to call Descartes an idiot there was nothing stopping me, and if I wanted to call you one there is a forum for that which I would have even linked to as necessary. Logical implication is one thing, but we can’t deal with logical implication in a general sense because we have no general sense until after we’ve made Descartes argument AND (conjunction) proved the existence of a Perfect Diety/Being which is what returns us to the real world. What we are left with is a “proof” that states, in no uncertain terms, that I, an existent greater than doubt, am, because I doubt. Which is to say, of course, that these are my doubts.

Then, disregarding causality, why would doubts imply a doubter?

162

i think that pretty much sums it up.

i’m still not clear why:

I thinks

isn’ the same as:

E(I) such that I thinks.

you agreed with me once, but now it seems you still don’t. how did descartes approach the problem, and why aren’t your proofs demonstrating his approach?

163

Sigh… There are several reasons that this all seems confused, particularly my perspective on things. It is largely because 1) every time I say something, somebody either doesn’t understand, or refutes it, and I have to necessarily say something at least a little bit different in reply, 2) I can’t remember what I said five minutes ago, much less 50 posts ago, and 3) the more we work this over, the better an understanding I have of the circumstances and thought processes here. This is, while terminally frustrating, as least a learning experience.

The lesser reason that the proofs are confused is, most of them are addressing different portions of the problem, and taking different slants, and sometimes the terminology gets shifted around to make a different point, or disputed. The greater reason is that, by the time you make the argument, any argument, you’re done. The proof’s finished, might as well go home. Shoehorn, if you will.

And the whole reason logical proofs aren’t convincing you people, is because they’re by nature entirely epistomological, and you guys are looking for something ontological.

Descartes was being epistomologically ontological (;)); he was thinking about existence. Now, his thoughts don’t cause, existence, of course; he can only effect his own knowledge of things. Descartes, in his own little head, decided to doubt everything and determine what, if anything, he could ‘not’ doubt.

Now, let’s take a short break and mention, ‘duh’ Descartes existed, or at least his mind did. This is obvious when you think about the alternative; non-existence, by definition, has no attributes and engages in no activity, not does anything that could be mistaken for activity. Since Descartes was sitting around thinking, he was ontologically on solid ground. He existed, or at least his mind did, as it was engaging in activites that were unbecoming to a non-existent thing.

Descartes, however, had not yet achieved epistomological awareness of his ontological existence. He was, in fact, busily doubting everything. You know all this. Eventually, he noticed that he was, in fact, thinking, and that this eliminated the possibility that he didn’t exist. Then he crafted that realization into a trite phrase and made his indelilble mark on civilization’s pool of trite phrases, that hardly anybody understands.

A person can say to themselves, ‘I walk’, or ‘I eat’, or ‘I sense’, or ‘I have a body’, and, epistomologically, have no reason whatsoever to believe that these are true assertions of fact. These are statements without basis, particularly if you’re already doubting everything *non-*mental.
However, the statement ‘I think’ gives us something more to work with. Even in a purely epistomological sphere, this statement can be verified. And, to make a short story short, from that conclusion, by the thrice-repeated argument, an epistomological awareness of one’s ontological existence can be attained.

Actual existence cannot be made, unmade, or otherwise effected by a merely mental process. What can be effected, is the knowledge that one exists. This knowledge, that ‘I am’, can only be assuredly obtained by first realizing the thought, ‘I think’.

Okay, everybody, the whole damned thing’s epistomological. And, epistomologically, ‘I think’ does indeedy imply ‘I am’. Have a nice night.

164

To confuse things a little furter, Descartes “deceiver” could have been even more deceitful.

He could be deceiving me that a thing cannot be true and false at the same time, laughing at my puny brain being deceitfully programmed with his nonsense logic and its inability to understand that it simulataneously exists and does not exist.

Like I said at the start, all “I am” demonstrates is that ontology is based on itself, like a snake biting its tail.

165

Well, not that the concept makes any sense, but if something simultaneously exists and does not exist, then, it does exist! :wink:

But more likely, that particular logical impossibility is really an impossibility.

The thing is, even if Descartes’ deceiver was scrambling my brains into mush, that is irrelevant. I cannot be decieved if there was not something, which exists, to deceive. If I truly did not exist, then I would have no awareness, not even an incorrect one.

And, like I said just now, the ‘I am’ in the Cogito is an epistomological statement, not an ontological one. We cannot know why we exist, as in what is the cause or source of our existence, by logical introspection. What Descartes was saying is that we can know that we exist; we can verify the ontological truth by epistomological means.

166

My point was that you are using logic and reason to evaluate the truth of the statement “I exist”. These epistemiologies might simply be systems of nonsense concocted by our devious deceiver, as might the concepts “truth” (“that which is clear and distinct” according to Descartes) and indeed “sense”.

167

And my point was that, by being the object of these deceptions, our existence is assured. Look at it this way: either we’re being massively decieved, or we’re not. If we’re not being massively deceived, then we can trust our thought processes (if not our senses), by which we can be certain that we exist. If we are being massively decieved, then our thought processes have no meaning, but we’re still the subject of a deciever. As the recipient of his deception, we must exist, so as to recieve the deception!

The interesting part about the situation you posit is, we cannot be as cetain about the assertion ‘I think’. Though we’re still having to think to assure ourselves of our existence, we could be jsut following a script of predesigned thoughts, as though our thoughts are just a transcript in a book, in which it is printed that it is self-aware, but which is not in fact self-aware.

The transcript of thoughts is mistaken when it asserts that it thinks, but not mistaken when it asserts that it exists, because, had it not existed, there would not even be so much as a printed assertion. On the extreme edge of doubt, we can still be certain of our existence.

168

If we assume we exist, we can have epistemological certainty of it. It is not any more stunning that assuming the axiom of choice and then saying the axiom of choice is true. Of course it is true: we assumed it.

169

Or both simultaneously.

Again I paraphrase eris by repeating: if we assume logic and reason as valid epistemiologies, then “cogito ergo sum” is true. They need not be.

170

begbert, I know you might feel a little overwhelmed here, but don’t despair. People still defend this argument. That’s the fun in philosophy: the arguments, not really where they lead :wink:

For one moderately pro case:
http://plato.stanford.edu/entries/descartes-epistemology/

171

it seems to me, and indeed it seems to be said in that article, that there is a way to formulate a sound argument that DOES demonstrate something.

let E(x) be “there exists an x”
let T(x) be “x is a thought”
let H(x) be “x is a thinker”
let st be “such that”

premises

  1. (E(x) st T(x)) -> (E(y) st H(y))
  2. E(t) st T(t)

conclusion:

E(I) st H(I).

i use “I” for convenience, here. this is a sound logical argument, and differs from yours in that it states the existence of everything it needs to in order to formulate a valid conclusion from valid premises.

examination of this shows why erislover said cartesians tend to wish for something more than just implication, that thought actually causes the thinker. you can see that the thought here comes before the thinker, and it is the thought that allows the thinker to exist.

my personal problem with this argument is that there is no reason to believe premise 2 in this context. sure, we know that thoughts exist, we have them all the time. but if we are not supposing first that we exist, it is very tricky to conclude that thoughts exist. this is why i will continue to accept as a fundamental axiom “i exist.”

172

oops i forgot:

the above formulation also gives no reason to suspect that I am the thinker whose existence is proved. if we conclude that it is i, we do so because it is i for whom the thoughts exist. but that places an “i” in the premises, which is what the proof necessarily avoids.

173

My algorithm:

  1. OBSERVE that ‘you think’
  2. From the DEFINITION of ‘existence’, determine that non-existent things do not think.
  3. CONCLUDE from the above two facts that the source of your thoughts must not be non-existent.

The only assumption that occurs in my argument is the definiton of existence, not my existence. I cannot reply to your statement, as I feel that it does not apply to anything.

From a formal symbolic logic standpoint, there are so many structural and logical problems with this, it would would pointless to try and enumerate them. Besides, we’ve kinda informally decided that using logic to discuss existence introduces more confusion than it solves. (Don’t ask me why. It’s not like speech is less ambiguous.) Given these facts, I think it’s just best to phrase your argument verbally:

Assuming:
1: (Something that is a thought, and exists) implies (something (else) that is a thinker, and exists)
2: (Something that is a thought, and exists)

We can conclude:
2: (Something (else) that is a thinker, and exists)

You are right about the non-proof of ‘I’ in this argument; I took them out for you.

I suppose I should thank you for your support, though all you’ve really said is, ‘a thought that exists implies a thinker that exists.’ This is old business, inherently obvious, and there are people who would dispute you anyway.

See my response to erislover to see my “current” statement of the argument.

Now, this is worth addressing!

There are two aspects to this problem; both have simple answers, believe it or not.

The first is, if my mind might be broken, can I conclude anything from the 0th-hand observation that I am thinking? The answer: yes. The content of the thought is irrelelavent, so long as we are thinking it. It can be white noise, so long as one senses that they are thinking. And, it doesn’t matter if a person is mistaken in thinking that they are thinking, either! Even if the thought that you incorrectly think you are perceiving doesn’t exist at all, and the thought with which you think you are noticing the thought is merely noise, then there is still some kind of activity going on. If there were no thoughts, then then there wouldn’t be any, nor illusions of them, nor mistakes about them. If you think you’re thinking, then you are. Though, you’re correct, you can’t vouch for the usefulness of your thoughts! :slight_smile:

The second effect of a scrambled mind, is wether it’s fair to expect any arguments you make to be useful at all! The answer is, sure, why not?

At several points in this excersise, we are considering conditions that, let’s just say, are not conduscive to the formulation of a rational argument. Wether decieved, logicless, mindless, or nonexistent, in all of these cases, no good argument. (In fact, in the final case, you wouldn’t make an incorrect argument; you would neither make an argument nor think you were making an argument. You simply wouldn’t exist.)

So, in the face of false logic, we do what we do with the other problematic cases: ignore them. Because if we don’t, we have no choice but to abondon the argument from the very start. And, that wouldn’t be any fun, would it? You might as well consider the options before deciding you’re a monkey, right? :smiley:

174

so, please tell me, who does the observing in this, if it is not assumed that you exist.

why don’t you give one example.

actually, i wasn’t proving the existence of something, as such. i was proving the existence of something that is a thinker, using existence as a second-order property, where its use is perfectly acceptable, and is used more than often in mathematical proofs.

i disputed it myself. the point remains that you can’t prove your own existence alone without assuming it beforehand. you have yet to demonstrate otherwise.

175

Sigh.

  1. You’re supposed to include line numbers and justifications for each line of your proof. Give or take the steps you skipped, yours are ‘premise’, ‘premise’, and ‘modus ponens on 1,2’.

  2. Non-standard infix operators (like your ‘st’) are not part of formal symbolic logic. I’ll get back to this.

  3. Formal symbolic logic is an exercise in symbolic replacement by defined rules. To use, say, a modus ponens transformation, the symbology must match exactly.

  4. Unqualified symbols (such as an ‘x’ outside of an Ax.( ) or Ex.( ) ) represent specific, constant objects. Oh, and each time you pull something in or out of a ‘for all x’ or a ‘there exists an x’, or change the symbology within one, takes a separate step.

  5. Fixing these is non-intuitive. The first premise seems clear:
    “Ex.( E(x) st T(x) ) -> Ey.( E(y) st H(y) )” (leaving the invalid ‘st’ construciton for a moment. But, the other premise seems harder. Are you trying to say,
    “At.( E(t) st T(t) )” (everything exists and thinks; doubtful) or
    “Et.( E(t) st T(t) )” (something exists and thinks; possibly) or
    “E(t) st T(t)” (the specific object ‘t’ exists and thinks; :dubious: ) or
    “E(I) st T(I)” (useful for the conclusion that you actually wrote) ?

  6. “Such that” has more problems. Take “E(t) st T(t)”, for an example. All the meaning that you (seem to) want out of it is inherent in the fact that the ‘t’ has both the ‘E’ property and the ‘T’ property. So, the (probably) proper way to write your second premise is “E(t) & T(t)”, or more likely “E(I) & T(I)”

  7. …but that opens up a whole new problem. (This one I like.) Given those (repaired) premises, I would write a rather different argument…

  8. Ex.( E(x) & T(x)) -> Ey.( E(y) & H(y) ) [premise]

  9. E(I) & T(I) [premise]

… wait for it …

:. E(I) [conjunction simplification on 2]

This is what we like to call, “begging the question”. As you can see, it is evil. I have no intention of doing it. In other words, I ain’t gonna include “I exist,” as an assumption for an argument with the conclusion “I exist”. Not gonna happen.

Now, in reality, some of the more clerical errors and omissions in your ‘proof’ would have been ignored, had you not challenged me to present one. The misused x’s and y’s, and especially the ‘st’ thing, plus the fact that we’ve had too many posts just like this one, led me to belive that a, ahem, ‘formal’ froof was not necessary to teh discussion.

The question-begging, though, is your real complaint.

Let us first look at the definition of ‘existence’
To quote the Merriam-Webster website (www.m-w.com)

I think that 2a is what we’re looking for, specifically. Are we, or are we not, figments of our own imaginations? As everybody knows, I can only speak to my own observations, so the rest of this argument will be in the first person. Try it at home.

If I don’t exist, then I must be imagining that I exist, or (in the case of a deciever or faulty logic) otherwise entertaining the mistaken notion of my own existence. (If a person is assuming that they don’t exist, then that assumption works too, as do any other thoughts.)

I am, therefore engaging in the action of making an assumption. This is not reasonably indisputable; after all, each of the disputations that I can come up with is another thought of mine.

I’d like to stress that it is not unreasonable to call these thoughts ‘mine’; to, in other words, retain the ‘I’. At the highest level I percieve them as my own; even if at some level they’re merely the manifestations of electrical transmissions among brain cells, at the operative level I am assigning them to me. Disputing this would be making an unnecessary personal redefinition of the term ‘I’.

So, it is an observable, and not reasonably doubtable fact that I think. You say, ‘fine, but only if I exist’. Hate to tell you this, but I am observing the fact that I think. It is not reasonably doubtable.

However, we’ll come at it your way. You like the assertion, “The existence of a thing is required for the thing to think.” Well, that seems fair enough. We can’t have non-existent things going around thinking; it’s bad for the economy. I’d like to look at your assertion logically; to help formalize it, note that it’s synonymous to, “For all things, if a given thing does not exist, then it does not think.” (Using your predicates, incidentally, that’s “Ax.( ~E(x) -> ~H(x) )”. Just so you know.)

All implications have what is called a contrapositive. If the implication is true, then so is its contrapositive, and similarly if they’re false; they have identical truth values. The contrapositive of ~E(x) -> ~H(x) is H(x) -> E(x), meaning that if we accept your axiom, then we similarly have to accept “Ax.( H(x) -> E(x) )”; in english: “For all things, if a given thing does think, then it does exist.”

I am a thing. I think. Therefore, by your reasonable assertion’s contrapositive (and podus ponens), I am. If I didn’t exist, then I could not be thinking that I was thinking, now could I?

176

:smiley: You see it now?

177

Bah, contexts. Get you every time. In my sad and twisted attempt to retain something of Ramanujan’s “formal” logic, I accidentally sabotaged my own point.

If you read the sentence above, You’ll see it starts with “For all things”, which I am obviously referring to. That correcponded to “Ax.(”, that is, for all things that exist within the universe of consideration. This includes things that don’t really exist, or that we’re unsure of. “Real” existence is E(x), the second-order property. The set of consideration includes all things that are theoretically imaginable, including even unicorns and math and honest politicians. I’m definitely theoretically imaginable. Different thing, and not an issue to my argument.

All that it requires to prove something’s “real” existence, as opposed to “imagined” existence, is the demonstration of a property that is not the product of your (or somebody else’s) imagination. As I am unable to conclude that my thoughts could be entirely a figment of their own imagination, I must exist so as to have the property of thinking.

178

And as I just invited everybody on the planet to come and tell me, “You are merely the figment of God’s imagination,” I would point out that what I meant with

was, that you don’t have to be the original source of the imagined idea for it to be imaginary. Say, if fred imagines that bugs are crawling all over him, just because you’re not imagining that he has bugs all over him, doesn’t imply that the bugs exist.

Still, that would be a valid point of consideration. What if I am a figment of God’s imagination? Response: depending on your definition of ‘I’, it’s not a problem.

If god is ‘play-acting’ you, isolating off a fracton of his vast consciousness and having it act out the thoughts that you are manifesting, then, by a basic definition, it is fair to say that you can claim God’s existence as your own! Of course, you should properly say that you are a fraction of god, but either way, You do exist.

If god is merely imagining to himself, “suppose there were a person,” then that would not imply that you exist. However, our observations of self-thought are not consistent with that idea. Something, which we call ‘I’, is actually generating specific thoughts. For that to carry itself out, there must be an actor in question; there must be a “real” existing thing that started the process of generating the thoughts. If it’s god, so be it, but we can still validly claim existence, though again it’s merely claiming our slice of God’s existence.

179

:smiley: So you see why it isn’t just implication?

180

Aaaurgh!! erislover, I have no idea what’s going through your head, but implications don’t imply causality, one way or the other. An implication expresses a correlation, if you like; a 100% effective correlation. A -> B doesn’t say that A causes B. A -> B doesn’t say that A doesn’t cause B.

And see why what isn’t just implication? The sentence you quoted is something akin to an assertion, not an implication. Conciseness is good and all, but there’s an art to it. :Ds are wonderful and all, but just because you’re having an epiphany, doesn’t mean the rest of us are going to have it too, just because you put a :smiley: down.