Justified true belief: knowledge and the myth of propositions

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Londoner
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Re: Justified true belief: knowledge and the myth of propositions

Post by Londoner » Thu Aug 03, 2017 9:33 am

Peter Holmes wrote:
Wed Aug 02, 2017 8:19 pm
Thanks. I'm afraid I disagree with all of this, partly for the reasons in my OP, which you don't address. You're explaining Descartes' theological motivation, but only by repeating his unjustified assertions. An argument is not evidence, and there is no evidence for an idea of a god 'that is already present in the mind'. This is reminiscent of the 'sensus divinitatis' that Plantinga falls back on - or of the ontological argument - or even of presuppositionalism. My position is that theism is irrational, so I don't suppose we can pursue this discussion to much purpose. But again, thanks.
You asked, of Descartes; Why do you say experiences are the only certain thing in his view? I explained Descartes position. If you disagree with what I wrote then that would be about whether I have given a true account of what Descartes said. Whether Descartes was correct is a different matter. I did not say he was.

That said, I think your objection is a bit odd. Descartes' argument refers back to Plato.

Regarding your other posts, I think I agree with much of what you write, but I had problems when you got to:
As you say, we establish the truth of 'the earth orbits the sun' by means of evidence. And I think this is an objective truth, independent of any belief or knowledge-claim, which the JTB truth condition acknowledges: S knows that p only if p is true. But no evidence that I'm aware of can establish the truth of 'a=a' or '2+2=4'. They are tautologies, so only vacuously true - reliable only because they are unfalsifiably correct and tell us nothing about reality - though we use them to say falsifiable things about features of reality.
I disagree that we do establish the truth of 'the earth orbits the sun' by means of evidence. That claim is also a tautology, in that it must follow from that evidence, however the evidence would also need to be established. And the evidence for the evidence, and so on. In the end, that 'truth' must either rest on something that we do not know to be true - in which case its truth is not 'established'. Or it must be circular, the 'truth' of the claim guarantees the truth of the evidence - and vice-versa.
My point is that inductive inference - where the premise(s) give us more or less convincing reasons to accept the conclusion, but don't entail the conclusion - is not the best that we can hope for when it comes to our empirical knowledge of reality. We can have objective knowledge of reality, expressed by factual assertions such as 'the earth orbits the sun', which can then be true premises in valid deductions with entailed conclusions. We aren't stuck with always insecure knowledge of reality. The problem of induction - that the future need not be like the past - doesn't affect the way things are now: the earth does orbit the sun - from which we can deduce true conclusions.
There, I do not understand where 'inductive inference' comes in. I understand 'induction' to involve inferences from the particular to the general. That step is a use we make of empirical knowledge, but it is not itself empirical. That (say) 'the future will be like the past' is a metaphysical claim. Perhaps you also think this, it doesn't seem entirely clear.

And in the first post:
There are features of reality; there is what we believe or know about them, such as that they are the case; and there is what we say about them, which may be true or false. To muddle these things up is a mistake.
I think they are always necessarily muddled. We cannot separate a 'features of reality' from 'what we say about them' (or 'think about them' would be better). First assuming there is a particular thing; 'reality', I can only encounter that 'reality' via my own mind and I can only express what is in my mind via language.

Discussions of what we mean by 'knowledge' or 'belief' have to operate within the muddle. It is no good constructing a definition of those words that refers to something external like 'objective knowledge' (the words used in your previous paragraph in the OP) because we never have it.

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Re: Justified true belief: knowledge and the myth of propositions

Post by Peter Holmes » Thu Aug 03, 2017 10:08 am

Thanks, Londoner. That's very useful and interesting. I have several questions about what you say that I need time to formulate - but I have to take a break for a while. Just wanted you to know I'm grateful for the time and care you've taken, and I hope to respond in time.

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Re: Justified true belief: knowledge and the myth of propositions

Post by Peter Holmes » Tue Jun 18, 2019 11:58 am

As a follow-up to my OP about the JTB definition of knowledge, and Gettier's criticism, I thought it worth posting here a related contribution I made to a discussion elsewhere about facts, categories and correspondence theories.

I'm pointing out that the way philosophers use the word 'fact' to mean 'feature of reality' is deeply confusing. Facts use categories, and there are no categories inherent in reality, but only things that can be categorised. You and I aren't facts - we're human beings.

Correspondence theories rest on the strange idea that features of reality 'correspond' to our ways of talking about them, as though the relationship is two-way. But it isn't, which is why for any one feature of reality, there is an infinitely flexible number of ways of talking about it - of 'facts' about it - according to what we want to say.

A radical distinction between what we say and what say it about is what I'm advocating, because the failure to make that distinction has befuddled philosophers for at least two and a half millennia.

And the myth of propositions has played a large part in that confusion. For example, the first JTB condition is: S knows that p iff p is true. What has knowing a feature of reality is the case anything to do with the truth of a proposition? That's completely back to front.

In the condition, the two 'p's have radically different functions: the second is a linguistic expression - so what is the first? - it's the same proposition. And that's the myth of propositions at work: mistaking what we say for the way things are.

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Re: Justified true belief: knowledge and the myth of propositions

Post by Skepdick » Tue Jun 18, 2019 12:15 pm

Peter Holmes wrote:
Tue Jun 18, 2019 11:58 am
A radical distinction between what we say and what say it about is what I'm advocating, because the failure to make that distinction has befuddled philosophers for at least two and a half millennia.
Anybody who subscribes to a deflationary theory of truth would say that this distinction is worthless in practice.

Do you have a habit of saying things, without your words referring to anything whatsoever? You don't. Your words always refer to something. Be it any particular human, the particular concept of a human, the language we use to speak about humans; or the particular concept of a concept itself.

In the language of CS Peirce, do you ever use signifiers which lack a signified? I don't. You don't either. Signifiers without a signified are meaningless. They are empty vessels.

So what is the intention of such distinction?

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Re: Justified true belief: knowledge and the myth of propositions

Post by RCSaunders » Tue Jun 18, 2019 8:26 pm

Peter Holmes wrote:
Wed Jul 26, 2017 2:13 pm
When we believe or know a feature of reality is the case, we do not believe or know a proposition. So we do not believe or know something that is true or false.
In what form does one consciously believe or know something? How is it possible to have a belief or knowledge about anything without the conscious conclusion, "A is sucn'n'such," or, "heavier than air flight is possible?" It is not a statement or proposition that is believed or known but what the proposition asserts. If nothing is asserted there is nothing to believe or know.

If one's assertion happens to be the actual case, that is, if heavier than air flight is possible, the assertion is true, and what we have asserted is therefore knowledge and not just a belief or assumption. This does not mean one cannot be mistaken about what they assert, as most people are most of time.

As an aside: You wrote: "So we do not believe or know something that is true or false." Of course if it's false it is not knowledge and if accepted as such is only a belief, or more likely, a superstition."

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Re: Justified true belief: knowledge and the myth of propositions

Post by RCSaunders » Tue Jun 18, 2019 9:08 pm

Peter Holmes wrote:
Wed Jul 26, 2017 2:13 pm
The Gettier problem ...
The real problem is JTB. It confuses the question of how what one believes can be known to be true knowledge with the question of what true knowledge is. There is only one thing that determines what is and what is not knowledge, reality.

All knowledge is held in the form of propositions which are statements about some aspect of reality. If what the proposition asserts is what that aspect of reality is, the proposition is true knowledge. If what the proposition asserts is not what that aspect of reality is, the proposition is false and not knowledge. One's knowledge consists of all the true propositions one holds in memory.

The test for true knowledge is always reality itself. If there is doubt about the veracity of a proposition, the aspect of reality asserted must be examined by whatever means possible, including how one came to the conclusion stated by the proposition. If it is not possible to determine the bases of the assertion or to test its veracity, the assertion must be held as 'possible but not certain' or 'doubtful.' In most cases, if an assertion about reality cannot be examined or tested, it has little importance since it apparently has no consequences.

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Re: Justified true belief: knowledge and the myth of propositions

Post by Skepdick » Tue Jun 18, 2019 10:08 pm

RCSaunders wrote:
Tue Jun 18, 2019 9:08 pm
Peter Holmes wrote:
Wed Jul 26, 2017 2:13 pm
The Gettier problem ...
The real problem is JTB. It confuses the question of how what one believes can be known to be true knowledge with the question of what true knowledge is. There is only one thing that determines what is and what is not knowledge, reality.
The real problem with JTB is its inability to deal with probabilities and the problem of induction, and as a result it admits trivial truisms as "knowledge" without being informative.

"Your airplane may or may not crash." meets the JTB criterion.

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Re: Justified true belief: knowledge and the myth of propositions

Post by RCSaunders » Wed Jun 19, 2019 12:59 am

surreptitious57 wrote:
Wed Jul 26, 2017 7:27 pm
For a truth claim to be considered knowledge it has to be supported by evidence or proof or logic. However because evidence is
the remit of science which is primarily an inductive discipline
...
What damage Hume has done to philosophy. The only part of science that can remotely be call, "inductive," is that which results in hypotheses. True science is identification and deduction.

The identification of the chemical elements and how they interact is entirely deductive. Once an element is identified and it properties defined, that element will always have those properties. If an element is discovered with different properties, no matter how similar to another element, it is a different element, because it has different properties.

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Re: Justified true belief: knowledge and the myth of propositions

Post by RCSaunders » Wed Jun 19, 2019 1:07 am

Londoner wrote:
Wed Aug 02, 2017 5:47 pm
The 'cogito' bit only tells us a subject exists, not that any particular sense experiences are valid in the sense of being true representations of the world.
Since your "sense experience" is the only consciousness of the world you have, if reality were different from the way you perceive it, you could never know it.

Fortunately, the reality you perceive is exactly as you perceive it.

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Re: Justified true belief: knowledge and the myth of propositions

Post by Skepdick » Wed Jun 19, 2019 1:36 am

RCSaunders wrote:
Wed Jun 19, 2019 12:59 am
surreptitious57 wrote:
Wed Jul 26, 2017 7:27 pm
For a truth claim to be considered knowledge it has to be supported by evidence or proof or logic. However because evidence is
the remit of science which is primarily an inductive discipline
...
What damage Hume has done to philosophy. The only part of science that can remotely be call, "inductive," is that which results in hypotheses. True science is identification and deduction.

The identification of the chemical elements and how they interact is entirely deductive. Once an element is identified and it properties defined, that element will always have those properties.
That is the fantasy of the Clockwork Universe.

The same element can exhibit different properties at different temperatures.

It puzzles me how people can still subscribe to the religion of deductive determinism in 2019.

Have you heard of the Bell Inequalities?

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Re: Justified true belief: knowledge and the myth of propositions

Post by RCSaunders » Wed Jun 19, 2019 2:30 am

Skepdick wrote:
Tue Jun 18, 2019 10:08 pm
The real problem with JTB is its inability to deal with probabilities and the problem of induction, and as a result it admits trivial truisms as "knowledge" without being informative.

"Your airplane may or may not crash." meets the JTB criterion.
I certainly don't support the JBT criteria, but I don't see why, "your airplane may or may not crash," would not be a true statement, since it is only asserting that the future cannot be predicted with an example.

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Re: Justified true belief: knowledge and the myth of propositions

Post by RCSaunders » Wed Jun 19, 2019 3:28 am

Skepdick wrote:
Wed Jun 19, 2019 1:36 am
RCSaunders wrote:
Wed Jun 19, 2019 12:59 am
surreptitious57 wrote:
Wed Jul 26, 2017 7:27 pm
For a truth claim to be considered knowledge it has to be supported by evidence or proof or logic. However because evidence is
the remit of science which is primarily an inductive discipline
...
The identification of the chemical elements and how they interact is entirely deductive. Once an element is identified and it properties defined, that element will always have those properties.
You didn't finish the quote. The remainder is: " If an element is discovered with different properties, no matter how similar to another element, it is a different element, because it has different properties."
Skepdick wrote:
Wed Jun 19, 2019 1:36 am
That is the fantasy of the Clockwork Universe.
It has nothing to do with determinism.
Skepdick wrote:
Wed Jun 19, 2019 1:36 am
The same element can exhibit different properties at different temperatures.
How any element will behave in any particular context or relation to other elements ARE its properties.
Skepdick wrote:
Wed Jun 19, 2019 1:36 am
It puzzles me how people can still subscribe to the religion of deductive determinism in 2019.
What is, "deductive determinism?" I don't believe in determinism as a universal principle.
Skepdick wrote:
Wed Jun 19, 2019 1:36 am
Have you heard of the Bell Inequalities?
Of course.

Have you heard of the chemical element sulfur? Are you aware of its attributes and characteristics? Sulfur is that which has the attributes and characteristics of sulfur. Anthying without those attributes and characteristics is not sulfur. Anything with different attributes and characteristics is not sulfur. Sulfur's attributes and characteristics do not make sulfur what it is, they do not cause it to be sulfur, they are what sulfur is, they are its identification.

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Re: Justified true belief: knowledge and the myth of propositions

Post by Skepdick » Wed Jun 19, 2019 7:35 am

RCSaunders wrote:
Wed Jun 19, 2019 2:30 am
I certainly don't support the JBT criteria, but I don't see why, "your airplane may or may not crash," would not be a true statement, since it is only asserting that the future cannot be predicted with an example.
So you agree that it's true. It's justified given there's plenty evidence that some airplanes crash and some don't.

How does it "not support" the JTB criterion then?

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Re: Justified true belief: knowledge and the myth of propositions

Post by Skepdick » Wed Jun 19, 2019 7:52 am

RCSaunders wrote:
Wed Jun 19, 2019 3:28 am
You didn't finish the quote. The remainder is: " If an element is discovered with different properties, no matter how similar to another element, it is a different element, because it has different properties."

How any element will behave in any particular context or relation to other elements ARE its properties.
So it's one element at temperature X and another element at temperature Y? That's not very coherent.

Could you show me where in the periodic table there is any mention of temperature?
RCSaunders wrote:
Wed Jun 19, 2019 3:28 am
It has nothing to do with determinism.

What is, "deductive determinism?" I don't believe in determinism as a universal principle.
Deduction promises 100% certainty e.g 0% chance of uncertainty.By any other name that's equivalent to determinism.

Hence I am using "deductive determinism" and "predictive determinism" synonymously.
RCSaunders wrote:
Wed Jun 19, 2019 3:28 am
Have you heard of the chemical element sulfur? Are you aware of its attributes and characteristics? Sulfur is that which has the attributes and characteristics of sulfur.
Could you give me a complete set of those attributes and characteristics? As a thought experiment: imagine there is an unknown substance on your desk. How would you go about determining whether it's sulfur or not?

In the absence of an actual tool to count protons/electrons surely you recognize that you are engaging in hypothesis-testing e.g induction. Because I've asked you to determine whether an anonymous substance is "sulfur" you are only testing two hypotheses:
1. It's sulfur
2. It's not sulfur

But if I asked you to identify an anonymous substance. Period. Suddenly your decision-space grew exponentially. You are taking identification for granted, when it's way more complex than you care to admit.

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Re: Justified true belief: knowledge and the myth of propositions

Post by RCSaunders » Wed Jun 19, 2019 2:17 pm

Skepdick wrote:
Wed Jun 19, 2019 7:35 am
So you agree that it's true. It's justified given there's plenty evidence that some airplanes crash and some don't.
Absolutely not. I agree the statement is true because the future cannot be predicted, ever. The statement would be true if no airplane had ever crashed, or if, up to now, they all had crashed.
Skepdick wrote:
Wed Jun 19, 2019 7:35 am
How does it "not support" the JTB criterion then?
Because it is based on a principle, not evidence.

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