Knowledge without Certainty

@ughaibu,

ughaibu wrote:

ACB wrote:
Do you agree that B's last answer is inconsistent with his first three?
I think this problem is imported with the JTB model of knowledge, because we cant know what's true, under that model.

regardless though we know that B's last answer is true

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@jeeprs,

jeeprs wrote:

Quote:
have given decisive argument to show that the major arguments in support of the view that knowledge implies certainly are all fallacious

And I think you're probably correct in many ways. I was just reading a recap of Popper's response to Hume's skepticism. Popper says that even though it is true that inductive reasoning has no demonstrable logical basis, the fact is that it works, and furthermore we are constitutionally inclined to expect it to work. So I guess Popper's view is a kind of pragmatism, in that, we will have a hypothesis, which, if not representing absolute truth, is at least sufficiently robust to account for a wide range of phenomena. So whether it provides or constitutes certainty is a moot point - and I guess this is what you are saying also, is it not?

But I also think that the whole discussion is very context-sensitive. For example it is possible to be certain beyond any reasonable doubt about facts such as the capital of France but this is not necessarily paradigmatic for all kinds of truth statements.

Induction does not provide certainty (in the Cartesian sense) because is if possible for the premises to be true and the conclusion false when inductive reasoning is used. This is, indeed, the criterion of inductive reasoning. It was exactly on this account that Descartes insisted that only deduction be permitted in order to support knowledge claims. This is not a moot point. Inductive reasoning cannot provide Cartesian certainty. This is also why if science affords us knowledge (which it does) it follows that knowledge does not imply certainty, because scientific knowledge does not imply certainty. I hope that argument is clear.

Certainty beyond a reasonable doubt is not what Descartes (and Plato) intended by certainty. They intended by certainty, certainty beyond any possible doubt. It is, of course, a criticism of that concept of certainty that certainty beyond any possible doubt is something which cannot be had. But that is something else again.

I think you are quite right about the context sensitivity of what is ordinarily required to support our claim to know (I am not here talking about certainty, but of knowledge). The support required is proportional to the stakes involved. For example, a verdict of guilty in a capital case requires much stronger support than a verdict of guilty where a parking ticket is involved. The stakes in the first are life and death, in the second, the stakes are comparatively trivial. It is for this reason that the standard of proof in American criminal law is proof beyond a reasonable doubt. But in American civil courts, the proof require is that of "preponderance of evidence". A much lower standard of proof, for in civil cases, only money is at stake. A very good book on this matter is, Knowledge and Practical Interests by Jason Stanley. But please notice that we are here talking about knowledge. We are not talking about certainty. It is very important to see this difference.

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@ACB,

ACB wrote:

kennethamy wrote:
It is just that the pragmatics of our talk about knowledge is not really the topic of this thread, and probably deserves its own thread.

So I am mistaken about the topic of my own thread? It's a bit like being mistaken about the content of one's own thoughts....

Let me be quite clear about this: I am not arguing that knowledge implies certainty. This point has been discussed ad nauseam in these forums, which is why I am not seeking to discuss it now. I fully agree with you that knowledge does not imply the impossibility of error.

What I am concerned with - in the context of epistemology - is the analysis of statements consisting of two contradictory (though possibly both true) parts. Consider the following:

1. It is raining, but I don't believe that.
2. It is raining, but I am not sure about that.
3. Paris is the capital of France, but I am not (absolutely) sure about that.

Do you agree that all the above sentences are self-contradictory, even if both parts of them are individually true?

Now consider the following dialogue:

A: Do you know that Paris is the capital of France?
B: Yes.
A: Does that imply that it is the capital of France?
B: Yes.
A: Is it the capital of France?
B: Yes.
A: Are you absolutely sure about that?
B: No.

Do you agree that B's last answer is inconsistent with his first three?

How can the sentence, "I is raining, but I do not believe it is raining" possibly be self-contradictory, for it could very well be true, and what could be true cannot be contradictory? The same does for, it is raining, but I am not sure about that. And the one about Paris too. None of those sentences could possibly be contradictory, for all of those sentences might be true.

In your dialogue, again, the same reply: it is certainly possible for me to know that Paris is the capital, to know that knowing it is the capital implies it is the capital, and yet for me not to be sure it is the capital. So those sentences are not inconsistent. Of course, on the other hand, if I uttered these sentences together, it would be weird, and would call for explanation. (And, in the looser sense of ordinary language, we might very well call a person who uttered them together, "inconsistent". But, naturally, calling a person "inconsistent" is different from calling what he said, "inconsistent" in the strict sense of, "it is impossible for all those sentences to be truth together".

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@ughaibu,

ughaibu wrote:

ACB wrote:
Do you agree that B's last answer is inconsistent with his first three?
I think this problem is imported with the JTB model of knowledge, because we cant know what's true, under that model.

But your post is inconsistent, since give the JTB model, when the those conditions of JTB are satisfied, for A, then A does, by definition, know that p is true. To have justified true belief simply is to know that what is believed it true. So how can what you say be true? What I think you mean (and this has been discussed at length before) is that the person who knows that p does not know he knows that p. But, as you can easily see (once I have brought it to your attention) that is an entirely different claim, since we can clearly know that p without knowing we know that p.

It also occurs to me that perhaps what you mean is that unless we know that we know that p, we ought not to claim that we know that p. So that even if we satisfy the conditions of knowing, we are not in a position to claim to know. Which is, if you come to think of it, a rather peculiar claim, although not outrageous, for there are other such cases. For example, even if we satisfy the conditions of being dead, we are not in a position to claim that we are dead. Nevertheless, if we satisfy the conditions of being dead, dead we are, even if we are not in a position to claim we are dead. And if we satisfy the conditions of knowing, then know we do, even if we are not in a position to claim that we know. However, I don't think you are right to believe that even if we satisfy the conditions of knowing, we are not in a position to claim we know unless we know we know, since we are in position to claim we know that p as long as we believe we know that p, even if we do not know we know that p.

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@kennethamy,

kennethamy wrote:

It also occurs to me that perhaps what you mean is that unless we know that we know that p, we ought not to claim that we know that p. So that even if we satisfy the conditions of knowing, we are not in a position to claim to know.

Yes - that is precisely the point of this thread.

kennethamy wrote:

However, I don't think you are right to believe that even if we satisfy the conditions of knowing, we are not in a position to claim we know unless we know we know, since we are in position to claim we know that p as long as we believe we know that p, even if we do not know we know that p.

But if we don't know we know, how can we tell when it is appropriate to claim we know? I suppose you will say that if we have only Cartesian doubt, we can safely claim to know. This is fine at a practical level, and of course it is something we do all the time, but it does present a logical problem.

1. Necessarily, if I know that Paris is the capital of France, it is the capital of France.

2. Therefore (since this is a necessary relation), if I know that Paris is the capital of France, it is certainly the capital. (Note: I cannot be certain that I know; but if I do in fact know, then it is certainly the capital.)

3. So if I claim to know, I am by implication claiming that it is certainly the capital.

4. But if someone then asks me whether I am absolutely certain it is, I must admit that I am not. I must admit that, actually, it is not certainly the capital.

5. So (by 3 and 4) I am committed to the contradictory claims that it both is, and is not, certainly the capital.

1 Reply

@ACB,

ACB wrote:

1. Knowledge is justified true belief.
2. We cannot be absolutely certain of any facts about the world.

Therefore, when I say "I know that Paris is the capital of France", I mean "I justifiably believe that Paris is the capital of France beyond reasonable doubt". In other words, "I justifiably believe it is so, but I could (theoretically) be wrong".

But I only know that Paris is the capital of France if it actually is. So if I say that I know it, I am asserting the following:

(a) Paris is the capital of France.
(b) I believe Paris is the capital of France, but I could be wrong.

Thus I am asserting:

(a) Paris is the capital of France.
(c) It may be false that Paris is the capital of France.

But (a) and (c) are contradictory. Necessarily, if Paris is the capital of France, it is true that it is the capital of France.

Therefore, if we assert that we know (rather than just "probably know") some empirical fact, we are implying a contradiction. We cannot meaningfully make a bald assertion that we know an empirical fact.

Let me be clear that if Paris is indeed the capital of France, then we do in fact know it. But, since there is theoretical doubt, it is contradictory to assert that we know it.

Any comments?

So if I say that I know it, I am asserting the following:

(a) Paris is the capital of France.
(b) I believe Paris is the capital of France, but I could be wrong.

Where does the "so" come from? In any case, that is not what you are asserting. You are asserting, at least, that your belief that Paris is the capital is true and justified. You are not asserting that you could be wrong. Why should you be asserting that?

(a) Paris is the capital of France.
(c) It may be false that Paris is the capital of France.

First, I did not say that it was true that Paris is the capital, and it may be false that Paris is the capital. I said that Paris is the capital, but it (still) might be false that Paris is the capital. (Let me just mention, because I do not want further to confuse the issue that there is a difference between "may be false" and "might be false". "May be false" means that there is actually some evidence that it is false. But "might be false" means only that it falsity is not self-contradictory. "Might" even according to the dictionary, indicates bare possibility). So, what is not contradictory is are, Paris is the capital, and it is logically possible that Paris is not the capital. And those two sentences not only do not contradict each other, but both of them are true. Since the first states that Paris is the capital, and the second merely states that it is not Paris is not the capital is not a self-contradiction. And both of those statements are true. Paris is the capital, and Paris is not the capital is not a self-contradiction.

Let me be clear that if Paris is indeed the capital of France, then we do in fact know it. But, since there is theoretical doubt, it is contradictory to assert that we know it.

First of all, it does not follow from the fact that Paris is the capital that anyone knows it is the capital. True propositions need not be known, although all propositions that are known are true. Again I do not know what a "theoretical doubt it", but let's suppose that (as Descartes argued ) if I believe that Paris is the capital, but if it is possible that I am dreaming, then I do not know that Paris is the capital. I think that argument is fallacious since the mere fact that I might be dreaming, and therefore, that I might be mistaken when I believe that Paris is the capital, is not a good reason for thinking that I do not know that Paris is the capital. And I say that (and please pardon me for repeating what I have said so many times before) the fact that I might be wrong is not (by itself) a reason for thinking that I am wrong , but only if I think I am wrong do I know know that Paris is the capital. And, no reason has been given to think that I am wrong. To repeat. The possibility of error is no reason for thinking I do not know what I believe I know. It is the actuality of error that is a reason for thinking I do not know what I believe I know. But the possibility of error is, of course, a good reason for thinking that I am not certain of what I believe I know. (I am certain that p, but I might be wrong, is self-contradictory) But I know that p but it is possible that I am wrong (for it is possible that p is false) is not a contradiction. I am afraid that despite your denials, you are confusing knowledge with certainty.

If you hold that when you assert that you know that p, but that it is possible that p is false, you are saying something contradictory, that is because you think that the sentence "it is possible that p is false" means not that it is logically possible that p is false, but that it is epistemically possible that p is false. But that is simply to misunderstand what is meant by asserting that p can be known, but it is possible that p is false.

Philosophy is hard.

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@ACB,

ACB wrote:

kennethamy wrote:
It also occurs to me that perhaps what you mean is that unless we know that we know that p, we ought not to claim that we know that p. So that even if we satisfy the conditions of knowing, we are not in a position to claim to know.

Yes - that is precisely the point of this thread.

kennethamy wrote:
However, I don't think you are right to believe that even if we satisfy the conditions of knowing, we are not in a position to claim we know unless we know we know, since we are in position to claim we know that p as long as we believe we know that p, even if we do not know we know that p.

But if we don't know we know, how can we tell when it is appropriate to claim we know? I suppose you will say that if we have only Cartesian doubt, we can safely claim to know. This is fine at a practical level, and of course it is something we do all the time, but it does present a logical problem.

1. Necessarily, if I know that Paris is the capital of France, it is the capital of France.

2. Therefore (since this is a necessary relation), if I know that Paris is the capital of France, it is certainly the capital. (Note: I cannot be certain that I know; but if I do in fact know, then it is certainly the capital.)

3. So if I claim to know, I am by implication claiming that it is certainly the capital.

4. But if someone then asks me whether I am absolutely certain it is, I must admit that I am not. I must admit that, actually, it is not certainly the capital.

5. So (by 3 and 4) I am committed to the contradictory claims that it both is, and is not, certainly the capital.

But consider; suppose that we are playing chess, and the conditions of checkmate are satisfied. That is, one of the kings is in check, and it has no legal move. If those conditions are satisfied, then we announce, "checkmate". No one would object that unless someone knows that the conditions of checkmate are satisfied, the player has not been checkmated. The player is checkmated just if the conditions of checkmate have been satisfied. There is no additional requirement that anyone know those conditions have been satisfied. Why then does not someone know that p, if only the conditions of knowing that p have been satisfied. Just as there is no additional requirement that in order for checkmate to occur, it be known that the conditions for checkmate have been satisfied, so there is not additional requirement that for someone to know that p, that it be known that the conditions of knowing that p have been satisfied. Suppose that the conditions of knowing that p are that p is believed, justified, and true (JTB) then when A believes that p, A's belief that p is justified, and p is true, then A knows that p. A need not know that his belief that p is both justified and true, in order for him to know that p. A need but satisfy the conditions. In other words, just as the chess player need not know that he is in checkmate to be in checkmate, so neither is it necessary for A to know that he knows for A to know. (Indeed, if you come to think of it, not only is it not necessary for A to know that he knows in order to know, but, on the contrary, A could not know he knows unless he already knows!).

We have the right to claim to know when, and if, we have met the conditions of knowing. It is not a further requirement of knowing that we know that we have met the conditions of knowing.

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@kennethamy,

kennethamy wrote:

We have the right to claim to know when, and if, we have met the conditions of knowing. It is not a further requirement of knowing that we know that we have met the conditions of knowing.

But you keep switching between the requirements of claiming to know and the requirements of knowing (see my underlinings above). If we have met the conditions of knowing, we do indeed have the right to claim to know; but how can we avail ourselves of this right if we do not know we have met the conditions of knowing? To use your chess example: in order to announce "checkmate" a player needs to know, or at least believe, that the conditions of checkmate have been satisfied (unless he/she calls "checkmate" at random). But in any case, chess is not a good analogy, because chess players are not required to examine the logical consistency of statements, whereas philosophers are. And there is nothing in chess that is equivalent to Cartesian doubt.

Which of the numbered steps of the argument in my previous post do you consider wrong?

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A Platonic footnote (one of a series Very Happy

)

Would it be possible that knowledge of some kinds is certain, and knowledge of other kinds is not.

Plato distinguished between different kinds of knowledge. I think the knowledge of geography would be categorized by him as pistis, knowledge of physical facts. This was regarded as being inferior to dianoia, knowledge of mathematical relations. Beyond this there was noesis, knowledge of the forms.

As we recall, Plato also believed that true knowledge was innate, and remembered, rather than acquired.

It is eminently possible that Plato would regard all such knowledge as knowledge of national capitals, place names, and so on, as a rather mundane affair about which absolute certainty is neither possible, nor particularly important. In the Platonic scheme of things, certainty was to be sought in matters which were of far greater significance, such as the origin and destiny of the soul.

Now I perfectly understand that this kind of thinking is archaic and the distinctions between the types of knowledge are not generally recognised in modern philosophy. That is why this is presented as 'a footnote'. Please consider it as such.

Another relevant notion is that of Cartesian anxiety.

Quote:

Cartesian anxiety refers to the notion that, ever since René Descartes promulgated his highly influential form of body-mind dualism, Western civilization has suffered from a longing for ontological certainty, or feeling that scientific methods, and especially the study of the world as a thing separate from ourselves, should be able to lead us to a firm and unchanging knowledge of ourselves and the world around us. The term is named after Descartes because of his well-known emphasis on "mind" as different from "body", "self" as different from "other".

Richard J. Bernstein is recognized as having coined the term in his 1983 book Beyond Objectivism and Relativism: Science, Hermeneutics, and Praxis.

From Wikipedia.

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Certainty. Isn't certainty just a feeling? What propositions are true minus relation to sensation/emotion? Tautologies. And contradictions are false. Why? Because it's pretty persuasive to say that cheese is cheese. It feels right.

For a long time it's seemed obvious to me that "knowledge" and "certainty" are utterly inseparable from feeling. I also argue that mathematics is grounded on intuitions. What are "intuitions"? Proof just seems to me like successful persuasion. If an argument persuades most everyone, it gets called a proof, and the madhouse or the policeman scoops up the dissident. Or the dissident is ignored.

You could argue that all knowledge is uncertain or that all is certain. It depends upon what one means by "certain." I suggest we are dealing with an emotional spectrum.

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@Reconstructo,

Reconstructo wrote:

You could argue that all knowledge is uncertain or that all is certain. It depends upon what one means by "certain."

It also depends on what one means by "knowledge", and that appears to be an irreducibly arbitrary matter.

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@ughaibu,

I agree. What does one mean by knowledge? That's the beauty of numbers. They have a relatively exact meaning compared to abstractions like "knowledge" and "certainty."

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@ACB,

ACB wrote:

kennethamy wrote:
We have the right to claim to know when, and if, we have met the conditions of knowing. It is not a further requirement of knowing that we know that we have met the conditions of knowing.

But you keep switching between the requirements of claiming to know and the requirements of knowing (see my underlinings above). If we have met the conditions of knowing, we do indeed have the right to claim to know; but how can we avail ourselves of this right if we do not know we have met the conditions of knowing? To use your chess example: in order to announce "checkmate" a player needs to know, or at least believe, that the conditions of checkmate have been satisfied (unless he/she calls "checkmate" at random). But in any case, chess is not a good analogy, because chess players are not required to examine the logical consistency of statements, whereas philosophers are. And there is nothing in chess that is equivalent to Cartesian doubt.

Which of the numbered steps of the argument in my previous post do you consider wrong?

As I understand you, your problem is no longer whether we can know that, for instance, Paris is the capital. But whether we ever have the right to claim we know that Paris is the capital? I would have thought we have the right to claim that we know that Paris is the capital when we have satisfied the conditions of knowing that Paris is the capital. Is your question now how we can tell we have satisfied the conditions of knowing so that we can legitimately claim that we know Paris is the capital? I don't think I have a general answer to that question except it seems to me that we can legitimately claim to know when we believe that we know. If I believe that my evidence that Paris is the capital is strong enough so that it is true that Paris is the capital of France, then I believe I know Paris is the capital, and consequently, I would not be misleading anyone by claiming to know that Paris is the capital. When I claim to know something I am giving my word that I have done enough "research" into the whether whether what I claim to know is true, to let others depend on my claim so that they can act on it. In this way, the claim to know is very much like promising to do something. In the case of promising to do something, I am also giving my word that believe that I will perform what I promise to do so that those to whom I make my promise will be able to rely on my promise. In either case, I should not give my word lightly, and if I do, neither my claims to know, nor my promises, will carry much weight. And neither will be trusted. In fact, Harry Prichard, the 20th century English philosopher went do far as never to say the words, "I promise" but always said, instead, "I fully intend" so that if it turned out that he could not perform what he promised to do, he could not be accused of breaking his promise. Of course, as people learned about this curlicue of Prichard's, when Prichard would utter the words, " I fully intend" others would simply discount it as a manner of speaking, and say to themselves, "Oh, that 's just good old Harry, being overly cautious again", and take him as actually promising only in Harry's own eccentric way of doing so. Similarly, I suppose that someone might adopt the policy of never claiming to know unless he was absolutely certain of the truth of what he claimed to know, and utter the words, "I firmly believe on good ground that p" so that if he turned out to be mistaken, he could not be accused of having claimed to know when he was unable to guarantee that what he claimed to know was true. But, as in Prichard's case of never actually saying the words, "I promise", but only, "I fully intend", people would soon cotton on to the curlicue of never claiming to know (saying the words, "I know" rather than the words, "I strongly believe". So, I don't think that such a policy would really have its desired effect. Although, it is true that just as if one said "I fully intend" where most people would say, "I promise" and for some reason one could not keep his word (he broke his leg) and if others rounded on him for not keeping his promise, he could always retort, "I never did say I promised; I said I fully intend". Similarly, if someone, rather than claiming to know (as would be normally claimed under similar circumstances) said, "I strongly believe, and I have excellent reasons for believing what I believe", and it turned out later that he was mistaken, he could defend himself by reminding others that he had not actually said that he knew, but only that he strongly believed, and had excellent reasons for his belief. But would any of this show that although people did know things, they were never in a position to claim that they knew what they know? I doubt it.

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@jeeprs,

jeeprs wrote:

A Platonic footnote (one of a series )

Would it be possible that knowledge of some kinds is certain, and knowledge of other kinds is not.

Yes, Of course, Descartes held that he was certain the he existed because it was not possible to believe both that one existed and not exist because one could not do anything (including believing) unless one existed. And Descartes seems to have believed that all of our beliefs about our inner mental states were, as a class of beliefs, certain. (One could not be in pain, and be mistaken about being in pain) so that for Descartes, the mind was an open book (unlike facts "outside of ourselves about the physical world" ) About our own internal occurrences, we could not be mistaken. (I, myself, in company with the great novelists, and many psychologists, do not think this is true). Plato, of course, notoriously held that only the Forms could be objects of knowledge, so that, for instance, we could not know that fire-engines were red, but could know that Red was red.

1 Reply

@ughaibu,

ughaibu wrote:

Reconstructo wrote:
You could argue that all knowledge is uncertain or that all is certain. It depends upon what one means by "certain."
It also depends on what one means by "knowledge", and that appears to be an irreducibly arbitrary matter.

Indeed. And it is also true that whether Brutus killed Caesar (rather than Caesar killed Brutus) depends (at least in part) on what one means by "Caesar", by "Brutus", and by "killed". So there is nothing special about whether knowledge is certain in this respect. Whatever you say depends on what you mean. But, of course, words have meanings quite independent of what individuals mean by them. I suppose I can mean by "the Sun sets in the West" that chickens lay eggs. But "the Sun sets in the West" doesn't mean, that chickens lay eggs. Not at least in English. What words in a language mean is a matter of convention, of course. But that does not mean that what words mean is arbitrary, as you say they are. If they were, then we could not correct what people (especially children) say. E.g. "You don' t mean that the judge was uninterested, what you mean is that the judge was disinterested". The fact that we consult dictionaries to settle disputes about meaning shows that the meanings of terms are not arbitrary, for if they were arbitrary, there could be no disputes about what a word means, and individuals would be the arbiters of the meaning of the words they use. But they clearly are not.

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@kennethamy,

I think Descartes was correct in that view, and one of the reasons he was such a landmark thinker in philosophy. And I suppose, in a broad sense, very much an inheritor of the platonist tradition, in that he sought to prove the connection between the apodictic nature of self-knowledge, and the mathematical realism that he derived from it.

As for Plato and the 'ideas' and 'forms', I suspect that very few (myself included, I hasten to point out) really know what he meant by them. (That would be a discussion I would like to have, but I think I need to do a bit more reading in the area.) But I think when you go back and look at the Dialogs, the kinds of questions that were often considered in them were not of the same type as those that are considered paradigmatic in these discussions.

So I think we are missing something in all of this. But do carry on.

1 Reply

@jeeprs,

jeeprs wrote:

I think Descartes was correct in that view, and one of the reasons he was such a landmark thinker in philosophy. And I suppose, in a broad sense, very much an inheritor of the platonist tradition, in that he sought to prove the connection between the apodictic nature of self-knowledge, and the mathematical realism that he derived from it.

As for Plato and the 'ideas' and 'forms', I suspect that very few (myself included, I hasten to point out) really know what he meant by them. (That would be a discussion I would like to have, but I think I need to do a bit more reading in the area.) But I think when you go back and look at the Dialogs, the kinds of questions that were often considered in them were not of the same type as those that are considered paradigmatic in these discussions.

So I think we are missing something in all of this. But do carry on.

It is a standard fact of human life that people often deceive themselves about their inner mental life. You have only to read novelists like Dostoyevski, or Stendhal, to realize that, if you don't already realize that from your ordinary social intercourse. (Or from reading Freud(.

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@kennethamy,

kennethamy wrote:

Indeed. . . . . .

For the purposes of this thread, knowledge has been defined as JTB, and as JTB includes "true", one can not know what is true under JTB. Accordingly, all non-trivial knowledge, under JTB, is uncertain. The question is whether or not that uncertainty prohibits claims of apparent certainty.

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@kennethamy,

No doubt people decieve themselves about all manner of things. And many of our deciepts are probably very comfortable for us, as well. But if deciept is possible, then so must truth be. For what is deciept but the lack of truth?

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@jeeprs,

jeeprs wrote:

No doubt people decieve themselves about all manner of things. And many of our deciepts are probably very comfortable for us, as well. But if deciept is possible, then so must truth be. For what is deciept but the lack of truth?

Self deceit is generally characterised as belief that both P and not-P.

1 Reply

Knowledge without Certainty

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