Justified true belief: knowledge and the myth of propositions

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

Post by Skepdick » Wed Jun 19, 2019 2:51 pm

RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
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.
I don't understand what you are saying. First you agree that the statement is true, then you argue that the statement 'would be true'. It's either true or it's not true.

The statement is true because of the laws of logic.

In logic, the law of excluded middle (or the principle of excluded middle) states that for any proposition, either that proposition is true or its negation is true.

It then follows that at least one of these two propositions is true:
P1: This airplane will crash
P2. This airplane will not crash

∴ P1 ∧ P2 ⇒ True
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
Because it is based on a principle, not evidence.
It is based on evidence.

Some airplanes crash. Fact
Some airplanes don't crash. Fact.

Therefore the sentence "This airplane will or will not crash." is a evidence-based truism. It meets the JTB criterion for knowledge.
Last edited by Skepdick on Wed Jun 19, 2019 3:01 pm, edited 3 times in total.

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

Post by RCSaunders » Wed Jun 19, 2019 2:59 pm

Skepdick wrote:
Wed Jun 19, 2019 7:52 am
So it's one element at temperature X and another element at temperature Y? That's not very coherent.
I'm going to suppose you are not being disingenuous here and state what is obvious. However an element behaves at different temperatures is its nature. The fact that water is a liquid above zero degrees C, and a solid below zero degrees C, does not make it two different elements as you well know. The fact that it has those two different states is an attribute of water.
Skepdick wrote:
Wed Jun 19, 2019 7:52 am
Could you show me where in the periodic table there is any mention of temperature?
I also doubt that this is an honest request. The purpose of the periodic table is not to identify every possible attribute of every element but to identify those attributes which differentiate individual elements form each other and from which all other attributes can be deduced. It is an epistemological function.
Skepdick wrote:
Wed Jun 19, 2019 7:52 am
Deduction promises 100% certainty e.g 0% chance of uncertainty.By any other name that's equivalent to determinism.
I did not know there was a God of deduction that promised its efficacy. Deduction does not promise anything. It is a method, like language, or mathematics, invented by human beings for identifying, epistemologically, what can be true and what cannot. There is no guarantee that reason will result in the truth. (Deduction is only the formalization of reason.) What is guaranteed is that a failure to reason correctly will not discover what is true. Deduction is psychological, not metaphysical.

Determinism is a concept about the nature of existence. It is metaphysical, not psychological. It happens to be correct about physical existence, but does not pertain to life, consciousness, or the human mind.

Deduction is not a claim of omniscience or infallibility.
Skepdick wrote:
Wed Jun 19, 2019 7:52 am
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?
Of course I wouldn't. If there were an unknown substance on my desk (actually a frequent occurrence--I have cats) why would I presume sulfur was a likely candidate?
Skepdick wrote:
Wed Jun 19, 2019 7:52 am
But if I asked you to identify an anonymous substance. Period. Suddenly your decision-space grew exponentially.
Actually the detection of sulfur is pretty easy. I'd use gas chromatography. If it was simply a yellow powder (or some red plasticky stuff) I'd try burning a little and smelling it. Sulfur dioxide has a very unique and distinctive smell.
Skepdick wrote:
Wed Jun 19, 2019 7:52 am
You are taking identification for granted, when it's way more complex than you care to admit.
Of course it's infinitely complex, but if you can think of a better way of understanding that complexity than by forming concepts that identify existents, please explain what it is.

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

Post by Skepdick » Sun Jun 23, 2019 1:05 pm

RCSaunders wrote:
Wed Jun 19, 2019 2:59 pm
The purpose of the periodic table is not to identify every possible attribute of every element but to identify those attributes which differentiate individual elements form each other
This is not entirely wrong, but it's not precise either. The purpose of the periodic table is to classify atoms into categories called "elements" using "number of protons" as a classification function.

Colloquially you can call this process sorting, or identification, disambiguation, or classification, or reduction. Same idea - different language.

In one language you could say that you are moving from the general towards the particular.
In the language of systems theory you would say that you are going from holism towards reductionism.

Why did Mendeleev CHOOSE to use "number of protons" and not "some other feature of atoms as a sorting function? That's a question for another time.
RCSaunders wrote:
Wed Jun 19, 2019 2:59 pm
from which all other attributes can be deduced. It is an epistemological function.
But this is incorrect. If you count 8 protons in an atom then you can SAY that it's Oxygen, but you cannot deduce "all other attributes" of this particular atom from its proton count.

Without taking any further measurements (additional information!) you cannot deduce whether this atom is ¹⁶Oxygen, ¹⁷Oxygen or ¹⁸Oxygen.
If you were to commit to the atom being ¹⁶Oxygen there would be 99.76% chance that you are correct (given its abundance) and 0.24% chance that you are wrong.
RCSaunders wrote:
Wed Jun 19, 2019 2:59 pm
I did not know there was a God of deduction that promised its efficacy. Deduction does not promise anything. It is a method, like language, or mathematics, invented by human beings for identifying, epistemologically, what can be true and what cannot. There is no guarantee that reason will result in the truth.
It is the exact same "God" which tells me that an atom with 8 protons is 99.76% likely to be ¹⁶Oxygen, while an atom with 14 protons is 0% likely to be Oxygen of any kind. The epistemic God of falsification.

By definition all deductive arguments have a property called validity.
In logic, an argument is valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false.

If an argument is not valid then it cannot be said that it is sound. If an argument is neither sound nor valid, then it cannot be said that it's "deduction" any more than it can be said that an atom that does not have 8 protons is oxygen. That is its defining property!

What your brain does cannot possibly be deduction because deduction mandates error-free conclusions and absolute certainty. By definition.
RCSaunders wrote:
Wed Jun 19, 2019 2:59 pm
Deduction is only the formalization of reason.
And it's wrong. Deduction is one aspect of reason. Categorization/classification is another.
RCSaunders wrote:
Wed Jun 19, 2019 2:59 pm
Determinism is a concept about the nature of existence. It is metaphysical, not psychological. It happens to be correct about physical existence, but does not pertain to life, consciousness, or the human mind.
It's not metaphysical. It's epistemic. In probability theory "determinism" means probability 0 or 1. Absolute certainty.
RCSaunders wrote:
Wed Jun 19, 2019 2:59 pm
Deduction is not a claim of omniscience or infallibility.
It implies it and mandates it by definition:
* Soundness mandates true premises
* Validity mandates error-free conclusions from true premises.

If you cannot satisfy both at the same time then it's not deduction, and there is no way to satisfy both without omniscience.
RCSaunders wrote:
Wed Jun 19, 2019 2:59 pm
Of course it's infinitely complex, but if you can think of a better way of understanding that complexity than by forming concepts that identify existents, please explain what it is.
That depends entirely on your epistemic criterions for "understanding" and "explaining".

Suppose that you made the claims "I can understand and explain the phenomenon called atoms". What do you think would be sufficient evidence to falsify your claim?

Personally - I don't care if science can explain anything. I don't want or need an explanation (a story about the past) - I want accurate predictive models that are directly relatable to human experience, and address human needs. Predictive models, logic, reason et all - they are only instrumental.

To what end? You decide.

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

Post by RCSaunders » Sun Jun 23, 2019 3:28 pm

Skepdick wrote:
Wed Jun 19, 2019 2:51 pm
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
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.
I don't understand what you are saying. First you agree that the statement is true, then you argue that the statement 'would be true'. It's either true or it's not true.
Duh. The sentence, "The statement would be true if no airplane had ever crashed, or if, up to now, they all had crashed," is subjunctive and simply means the statement is true independent of any previous event. It is true simply because the future cannot be predicted. It is true even if every plane attempting to fly crashed in the past, the next one might not. It is true if no plane had ever crashed in the past, the next one might.
Skepdick wrote:
Wed Jun 19, 2019 2:51 pm
The statement is true because of the laws of logic.
Nothing is true because of the, "laws of logic." Logic is just a method. The so-called "laws of logic," are only a description about how the method is to be used to be useful.
Skepdick wrote:
Wed Jun 19, 2019 2:51 pm
In logic, the law of excluded middle (or the principle of excluded middle) states that for any proposition, either that proposition is true or its negation is true.
Of course that is how logic must be understood and used if it is to achieve its purpose. It is not a principle by which truth can be established, however. The proposition, "John's sister is his daughter's aunt," is not true, and neither is its converse, because John does not have any children.
Skepdick wrote:
Wed Jun 19, 2019 2:51 pm
It then follows that at least one of these two propositions is true:
P1: This airplane will crash
P2. This airplane will not crash
Ah, we get to the meat of the problem. No future proposition is true or false because all future propositions are not statements of fact (what is), but statements of a supposition (what might or could be).

I'll make it simple. The statement, "the plane crashed," must be either true or false because it is about a fact, something that actually happened. The statement, "the plane will crash," cannot be either true or false because it is only a guess.
Skepdick wrote:
Wed Jun 19, 2019 2:51 pm
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
Because it is based on a principle, not evidence.
It is based on evidence.

Some airplanes crash. Fact
Some airplanes don't crash. Fact.

Therefore the sentence "This airplane will or will not crash." is a evidence-based truism. It meets the JTB criterion for knowledge.
If you were talking about the very first plane ever built and attempted to be flown, the statement, "This airplane will or will not crash," would be (subjunctive for is) true. It has nothing to do with evidence.

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

Post by Skepdick » Sun Jun 23, 2019 3:55 pm

RCSaunders wrote:
Sun Jun 23, 2019 3:28 pm
Duh. The sentence, "The statement would be true if no airplane had ever crashed, or if, up to now, they all had crashed," is subjunctive and simply means the statement is true independent of any previous event. It is true simply because the future cannot be predicted. It is true even if every plane attempting to fly crashed in the past, the next one might not. It is true if no plane had ever crashed in the past, the next one might.
You are making up your own goal posts now. I think the technical term for this is "apologetics"?
JTB makes no stipulation whatsoever as to WHY a statement of belief is true. JTB only stipulates THAT a statement of belief is true. Which you have conceded is the case.

All that remains to be determined is whether the true belief is justified.
RCSaunders wrote:
Sun Jun 23, 2019 3:28 pm
The proposition, "John's sister is his daughter's aunt," is not true, and neither is its converse, because John does not have any children.
Great! Then do the same for my claim. Tell me why the proposition "my airplane may or may not crash" is not true, or concede that it is.
RCSaunders wrote:
Sun Jun 23, 2019 3:28 pm
Ah, we get to the meat of the problem. No future proposition is true or false because all future propositions are not statements of fact (what is), but statements of a supposition (what might or could be).
You are making stuff up again. Where does it say that propositions cannot be made about future events?
The Gettier problems make propositions about future events too.

This is a metaphysical disagreement. Does the future exist? Of course it does. And so - we can make claims about it.
RCSaunders wrote:
Sun Jun 23, 2019 3:28 pm
I'll make it simple. The statement, "the plane crashed," must be either true or false because it is about a fact, something that actually happened. The statement, "the plane will crash," cannot be either true or false because it is only a guess.
Strawman. The statement "the plane crashed" must be either true or false, and the statement "the plane will crash" will be either true or false. You can simply suspend judgment.

I agree with you that individually the truth-value of any one of the two propositions cannot be ascertained.
But holistically the truth-value of the proposition "this airplane may or may not crash" cannot be doubted.

It's true because it's a truism. It makes an all-exhaustive claim about the possible outcomes of an airplane flight. Your temporal objection is a non-sequitur.
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
If you were talking about the very first plane ever built and attempted to be flown, the statement, "This airplane will or will not crash," would be (subjunctive for is) true. It has nothing to do with evidence.
Non-sequitur. I am using two separate facts for my argument. One is the fact that some airplanes crash. The other is the fact that some airplanes don't crash. And I am using those facts as the basis of my proposition for every airplane that is currently in service.

The statement "this airplane may or may not crash on its next flight" is true. For every airplane. It is Justified True Belief. And therefore - it's knowledge.

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

Post by RCSaunders » Sun Jun 23, 2019 7:02 pm

Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
Great! Then do the same for my claim. Tell me why the proposition "my airplane may or may not crash" is not true, or concede that it is.
You haven't been paying attention. At least three times I said it was true.
Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
Where does it say that propositions cannot be made about future events?
What do you mean, "where does it say...?" Is there a, "Bible," of epistemology, or logic you refer to. Use your own mind and you'll know why it's true.
Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
The Gettier problems make propositions about future events too.
That's exactly what I mean. Instead of leaning on what someone else says, think for yourself.
Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
This is a metaphysical disagreement. Does the future exist? Of course it does. And so - we can make claims about it.
You are right, it is a metaphysical disagreement. The future, like the past exists only as a concept, it does not exist metaphysically. Only what is exists. To determine if something exists it is only necessary to ask if it is.

The future, like the past, is not a thing, entity, or substance, it is the concept for the relationship between that which was (past), and that which will be (future). Things and events can be past, that which was, and things and events can be future, that which will be; that is all that past and future mean. Past and future have no metaphysical existence.
Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
RCSaunders wrote:
Sun Jun 23, 2019 3:28 pm
I'll make it simple. The statement, "the plane crashed," must be either true or false because it is about a fact, something that actually happened. The statement, "the plane will crash," cannot be either true or false because it is only a guess.
The statement "the plane crashed" must be either true or false, and the statement "the plane will crash" will be either true or false.
You're getting closer. "The statement "the plane crashed" must be either true or false, ... " is correct as I stated, but you have changed this and perhaps did not notice, "...and the statement "the plane will crash" will be either true or false." That is also correct now that you have changed it to will be. It will be true once the plane has either flown successfully or unsuccessfully, but is not true until then.
Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
I agree with you that individually the truth-value of any one of the two propositions cannot be ascertained.
But holistically the truth-value of the proposition "this airplane may or may not crash" cannot be doubted.
I never said it could be doubted. I said it was true, but could not be true based on evidence, because there actually is none. I have no idea what, "holistically," means in this context. I know it's nonsense in every context I've ever seen it used.
Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
If you were talking about the very first plane ever built and attempted to be flown, the statement, "This airplane will or will not crash," would be (subjunctive for is) true. It has nothing to do with evidence.
I am using two separate facts for my argument. One is the fact that some airplanes crash. The other is the fact that some airplanes don't crash. And I am using those facts as the basis of my proposition for every airplane that is currently in service.
The facts are totally irrelevant. If there had never been a plane before, wouldn't it still be true that the first plane ever will either fly or crash? If every plane there ever was flew without crashing, wouldn't it still be true that the next plane that flew might crash?
Skepdick wrote:
Sun Jun 23, 2019 3:55 pm
The statement "this airplane may or may not crash on its next flight" is true. For every airplane.
I think this may be the crux of the disagreement. I agree and have all along that, "this airplane may or may not crash on its next flight," is true. Notice the statement is future possibility: may or may not, not an assertion of present fact: will or will not.
It is your earlier statement I disagreed with:
It then follows that at least one of these two propositions is true:
P1: This airplane will crash
P2. This airplane will not crash
I disagreed because it say one of the two proposition is true. If you had said, one of these propositions will be true, I would have agreed with it.

It would have been better, in that case to say:

At least one of these two propositions will be true:
P1: This airplane did crash.
P2. This airplane did not crash.

That is true and it requires no other evidence.

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

Post by Skepdick » Sun Jun 23, 2019 7:42 pm

RCSaunders wrote:
Sun Jun 23, 2019 7:02 pm
You haven't been paying attention. At least three times I said it was true.
Great! Then it satisfies the TB part of JTB. Onwards....

RCSaunders wrote:
Sun Jun 23, 2019 7:02 pm
That's exactly what I mean. Instead of leaning on what someone else says, think for yourself.
Which is precisely why I am doing when I am questioning why you ignore the existence of the future.
I am making propositional statements about the future - which is perfectly acceptable in my epistemology. And you are the one who is telling me that I am not "allowed" to think that way.

What gives?
RCSaunders wrote:
Sun Jun 23, 2019 7:02 pm
The future, like the past, is not a thing, entity, or substance, it is the concept for the relationship between that which was (past), and that which will be (future). Things and events can be past, that which was, and things and events can be future, that which will be; that is all that past and future mean. Past and future have no metaphysical existence.
This is going on a tangent. I am simply pointing out that there's no authority on any epistemology and so I can make propositions about the future. And the truth-value of such propositions can be verified in the future.

Predictions! We call them predictions. Which is how some knowledge works. Cause -> Effect.
If I kick you in the shins - then I predict you will experience pain.
RCSaunders wrote:
Sun Jun 23, 2019 3:28 pm
You're getting closer. "The statement "the plane crashed" must be either true or false, ... " is correct as I stated, but you have changed this and perhaps did not notice, "...and the statement "the plane will crash" will be either true or false." That is also correct now that you have changed it to will be. It will be true once the plane has either flown successfully or unsuccessfully, but is not true until then.
And you are continuing with your reductionist strawman. I am not addressing the individual claim "this plane WILL crash".
I also not addressing the individual claim "this plane will NOT crash" either.

I am addressing this, specific and HOLISTIC claim "this plane may or may not crash". It's a single proposition which can be formalized as a probability distribution. It is perfectly valid and testable. It's also a truism because all probabilities add up to 1.

However, your continued attempts to split up the sentence into something else is what I call reductionism.
My proposition is that this airplane may or may not crash. Which you have agreed is true.

There's nothing more to say about it as far as JTB is concerned.
RCSaunders wrote:
Sun Jun 23, 2019 3:28 pm
could not be true based on evidence, because there actually is none.
What the hell do you mean there is no evidence? Here is the data for all airplane crashes since 1970.
Here is the number of aviation industry flights since 2014.

My proposition about the future is based about evidence from the past. This is how ALL of fucking science works! Don't tell me you reject science?
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
The facts are totally irrelevant. If there had never been a plane before, wouldn't it still be true that the first plane ever will either fly or crash? If every plane there ever was flew without crashing, wouldn't it still be true that the next plane that flew might crash?
I don't understand what your point is. Yes - the claim is true. We already agreed that it's true. Why are you still discussing the T of JTB when you have already conceded it?
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
I think this may be the crux of the disagreement. I agree and have all along that, "this airplane may or may not crash on its next flight," is true. Notice the statement is future possibility: may or may not, not an assertion of present fact: will or will not.
I know that you did. You have agreed that my belief justifies the TB components of JTB.
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
I disagreed because it say one of the two proposition is true. If you had said, one of these propositions will be true, I would have agreed with it.
This is a non-sequitur. JTB doesn't prescribe anything to this effect - you are making up rules.
RCSaunders wrote:
Wed Jun 19, 2019 2:17 pm
It would have been better, in that case to say:

At least one of these two propositions will be true:
P1: This airplane did crash.
P2. This airplane did not crash.

That is true and it requires no other evidence.
You are nit-picking. DESPITE having conceded that my belief is true. I don't understand what more needs to be said here?
JTB doesn't care about WHY a belief is true. It only cares THAT a belief is true. My belief is true (which you have conceded!)
And my belief is justified (given all the evidence I have furnished you with).

Therefore my belief meets the JTB criterion for knowledge. Case closed.

I fully understand and acknowledge that this is worthless knowledge and I would gladly exchange this knowledge for toilet paper (if anybody were so stupid as to barter with me).

But my opinion on the matter is irrelevant. IF you subscribe and accept JTB as the correct description of knowledge, then you need to accept that my claim "this airplane may or may not crash" satisfies JTB.

Which is precisely what makes JTB a piss-poor epistemic theory. It trivialises prediction, which is an incredibly important property of knowledge.

But then again - epistemology hasn't solved the problem of criterion. And it's not going to any time soon...

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

Post by A_Seagull » Tue Jul 09, 2019 11:25 am

RCSaunders wrote:
Sun Jun 23, 2019 7:02 pm
It would have been better, in that case to say:

At least one of these two propositions will be true:
P1: This airplane did crash.
P2. This airplane did not crash.

That is true and it requires no other evidence.
Are you aware that you are making a lot of assumptions in your claim that this is 'true'?

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

Post by RCSaunders » Tue Jul 09, 2019 2:04 pm

A_Seagull wrote:
Tue Jul 09, 2019 11:25 am
RCSaunders wrote:
Sun Jun 23, 2019 7:02 pm
It would have been better, in that case to say:

At least one of these two propositions will be true:
P1: This airplane did crash.
P2. This airplane did not crash.

That is true and it requires no other evidence.
Are you aware that you are making a lot of assumptions in your claim that this is 'true'?
A, "lot of assumptions?" Perhaps you can name some of them.

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

Post by A_Seagull » Tue Jul 09, 2019 10:20 pm

RCSaunders wrote:
Tue Jul 09, 2019 2:04 pm
A_Seagull wrote:
Tue Jul 09, 2019 11:25 am
RCSaunders wrote:
Sun Jun 23, 2019 7:02 pm
It would have been better, in that case to say:

At least one of these two propositions will be true:
P1: This airplane did crash.
P2. This airplane did not crash.

That is true and it requires no other evidence.
Are you aware that you are making a lot of assumptions in your claim that this is 'true'?
A, "lot of assumptions?" Perhaps you can name some of them.
Well I don't know what process of inference you used to arrive at your conclusion so I cannot unambiguously identify what assumptions you used.. so if you can identify what process of inference you used.. then I could help to identify the assumptions.

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

Post by RCSaunders » Wed Jul 10, 2019 1:17 am

A_Seagull wrote:
Tue Jul 09, 2019 10:20 pm
Well I don't know what process of inference you used to arrive at your conclusion so I cannot unambiguously identify what assumptions you used.. so if you can identify what process of inference you used.. then I could help to identify the assumptions.
Why would I need your help. Your the one that asserted, "... you are making a lot of assumptions in your claim that this is 'true'?" When I ask you to name some you gave me some song and dance about why you couldn't. If you can't name any assumptions, why did you accuse me of making them.

There was no, "process of inference." It is simply an example of non-contradiction in a huopthetical case. After a plane has flown, if it crashed the statement, "This airplane did crash," will be true. If the plane didn't crash, the statement, "This airplane did not crash," will be true. After the plane has flown both statements cannot be true, consequently, "one of these two propositions is true." The original statement was that this would be the case after the plane flew.

Nothing at all is assumed unless you call the fact that two contradictory statements cannot both be true an assumption. (Excluded middle.)

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

Post by A_Seagull » Wed Jul 10, 2019 5:17 am

RCSaunders wrote:
Wed Jul 10, 2019 1:17 am
A_Seagull wrote:
Tue Jul 09, 2019 10:20 pm
Well I don't know what process of inference you used to arrive at your conclusion so I cannot unambiguously identify what assumptions you used.. so if you can identify what process of inference you used.. then I could help to identify the assumptions.
Why would I need your help. Your the one that asserted, "... you are making a lot of assumptions in your claim that this is 'true'?" When I ask you to name some you gave me some song and dance about why you couldn't. If you can't name any assumptions, why did you accuse me of making them.

There was no, "process of inference." It is simply an example of non-contradiction in a huopthetical case. After a plane has flown, if it crashed the statement, "This airplane did crash," will be true. If the plane didn't crash, the statement, "This airplane did not crash," will be true. After the plane has flown both statements cannot be true, consequently, "one of these two propositions is true." The original statement was that this would be the case after the plane flew.

Nothing at all is assumed unless you call the fact that two contradictory statements cannot both be true an assumption. (Excluded middle.)
You don't seem to be particularly interested in exploring the assumptions inherent in your claim..... and that is fair enough.

So I will just conclude with this: There are some truths of the world such as 'Then Earth goes around the Sun in an elliptical orbit' and 'e**ip=-1', and these truths can be demonstrated from a few simple assumptions and a fairly complex sequence of inferences; but to claim that some banal statement like your 'either some fictional aeroplane crashes or it doesn't' should fit alongside them as a truth of the world is just pathetic.

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

Post by Skepdick » Wed Jul 10, 2019 8:32 am

A_Seagull wrote:
Wed Jul 10, 2019 5:17 am
There are some truths of the world such as 'Then Earth goes around the Sun in an elliptical orbit
"Earth goes around the Sun in an elliptical orbit" is a conceptual truth. It describes potentiality, not actuality.

The elliptical equation which describes Earth's orbit, only tells you Earth's POTENTIAL position around the Sun.

The equation tells you nothing about Earth's ACTUAL position along the ellipse's circumference at any given point in time.
A_Seagull wrote:
Wed Jul 10, 2019 5:17 am
but to claim that some banal statement like your 'either some fictional aeroplane crashes or it doesn't' should fit alongside them as a truth of the world is just pathetic.
Why is it banal? It tells you the exact same thing as Earth's elliptical orbit. It enumerates potential possibilities, without telling you anything actual.

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

Post by RCSaunders » Wed Jul 10, 2019 8:21 pm

A_Seagull wrote:
Wed Jul 10, 2019 5:17 am
So I will just conclude with this: There are some truths of the world such as 'Then Earth goes around the Sun in an elliptical orbit' and 'e**ip=-1', and these truths can be demonstrated from a few simple assumptions and a fairly complex sequence of inferences; but to claim that some banal statement like your 'either some fictional aeroplane crashes or it doesn't' should fit alongside them as a truth of the world is just pathetic.
I totally agree. Except there is no claim the statement was about a physical fact. It is about the nature of reason itself.

Just as 2 plus 2 equals 4 is not a statement about any actual earthly fact, it is said to be true because two of anything added to two more is four, without specifying any actual things.

Euler's identity is not about any physical fact either. The mathematical elements, e, i, and π are all purely concepetual and have no physical existence. e and π are both irrational which means there is no commensurate (physical) unit of measure in which they can be expressed. i does not exist at all except as a concept.

In logic, the law of excluded middle states that for any proposition, either that proposition is true or its negation is true. It is one of the so called three laws of thought, along with the law of noncontradiction, and the law of identity. The law of excluded middle is the basis of the discussion you objected to.

The law of excluded middle is not based on an assumption, it is based on an axiom, that a thing is what it is and cannot be anything else. An axiom (not the nonsense proposed by modern day philosophers) is true because to deny it is self-contradictory. If you were not who and what you are you would be something and someone else. You could not be that and be you too. An assumption is something simply posited without conclusive evidence or reason. If you are satisfied with assumptions, fine, I am not.

I have no idea why you are uncomfortable with this reasoning, but if you are, then just ignore what I've written, and believe what you wish, but understand I will do the same.

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

Post by surreptitious57 » Wed Jul 10, 2019 10:12 pm

Skepdick wrote:
Earth goes around the Sun in an elliptical orbit is a conceptual truth . It describes potentiality not actuality

The elliptical equation which describes Earths orbit only tells you Earths POTENTIAL position around the Sun

The equation tells you nothing about Earths ACTUAL position along the ellipses circumference at any given point in time

It tells you the exact same thing as Earths elliptical orbit . It enumerates potential possibilities without telling you anything actual
One could say Earth goes around the Sun in an elliptical orbit is an empirical statement and so therefore does describe actuality
Furthermore Earth has been orbiting the Sun for four and a half billion years so its actual trajectory can very easily be determined

The equation may pertain to the general not the specific but the precise distance between Earth and the Sun can still be determined at any time
Nothing can have a perfectly circular orbit anyway since everything is in a constant state of motion and so any orbit by default has to be elliptical

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