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Re: Knowledge and belief



Lojbab:
>Newton knew that his 3 laws of motion were true

Presupposition: his 3 laws of motion were true.

Unless your claim is "Newton's 3 laws of motion were
not true, but he knew that they were true". That claim is
not normal in standard English, as far as I can tell.

[It is another issue whether the laws were or were not
true. They are valid in their domain of application. I don't
know what do you want to call a true scientific law.]

 >Einstein knew that the 3 Newtonian Laws of motion are false.

Presupposition: the 3 Newtonian Laws of motion are false.

I would tend to disagree with both your presuppositions,
but that's rather beside the point we're discussing. Why don't
we stick to everyday examples?

Suppose that somehow I become convinced that you have
three children. Would you make the claim "Jorge knows that
I have three children"? Would you make the claim "Jorge is
convinced that I have three children"?

 >Part of the trick here is the use of the past tense, which in English
>can change truth conditions.

I don't think that changes much. "Jorge knew that I have
three children" is equally unacceptable.

> I can know something ttoday and not know it
>tomorrow either because I forgot it or because I found out that my
knowledge
>was false or because the fact of the matter has changed since I knew it

The last one is irrelevant, you're changing the x2 sumti. The first one
is true, nobody said that if you know something you know it forever.
On the other hand, if you find out that your purported knowledge was
false, you would not keep claiming that you knew it. Would you really
accept something like: "I know that lojbab has two children, but
I knew that he has three". I don't think so. On the other hand: "I am
convinced that lojbab has two children, but I was convinced that
he has three" is perfectly acceptable.

 >Newton knew that for every action there is an equal and opposite reaction

Presupposition: for every action there is an equal and opposite reaction.

 >The  6 th grade student knows that for every action there is an equal and
> opposite reaction


Presupposition: for every action there is an equal and opposite reaction.
Or did you mean to claim something like:

    It is not the case that for every action ..., but the student knows
    that it is the case.

I don't think that works.

 >Now I have to confess that I don't actually know if Einsteinian relativity
>renders all of Newton's Laws false, because although I was a phsyics major
>(actually astrophysics, though I met the degree requirments for a phsyics
>major as well), I managed to avoid any solid exposure to relativity theory.

That doesn't matter. Why don't we use examples that are easier to
understand, so that we don't get entangled with philosophy of science
questions that don't have much to do with the issue.

 >That is, unless someone reading this corrects or contests the statements
>that Newton's Laws of motion are true or false at the present time, all
>of my statements above remain unchancged truth functionally by my admission
>of uncertainty as to the truth of what they claimn is known.  So my
knowledge
>as speaker is not necessarily relevant to the truth of a claim of someone
>else's knowledge.

You're right, it is not your knowledge as speaker that counts. What
counts is whether the presupposition is true or not. We expect of
speakers that they believe their presuppositions to be true,
but nobody can force that on you. You can make statements
hoping that they somehow turn out to be true, but if you do that too
often people will start to not take them seriously.

>And I contend that the absence of epistemology as a required component in
>a knowledge statement in English means that my two statements regarding
>the knowledge of the 6th grader and the college phsyics major can both be
>true regardless of the actual truth of the proposition.

That I disagree with. They can both be true, yes, but not regardless of
the truth of the proposition. Each needs its presupposition to be true.

>The result is that statements of knowledge become truth-functional
>equivalents of "is convinced of".

That's just not so. "She knows that you have three children" is not
truth-functionally equivalent with "she is convinced that you have three
children". If you accept both as true, then you speak a different brand
of English than most other people.

>WE accept that one can be convinced of something that eveyone else knows to
>be false because that one person may be blind to a counterdemonstration.
>The question is whether that individual can be said to "know" that fact
>that everyone else knows is false.  Given my arguments regarding 6th grade
>students, I am not sure this is untenable.

It is untenable, as far as I understand normal usage.

>Carrying to a greater extreme, we can have
>"the baby knows that the mother is about to feed her".

Yes. Presupposition: the mother is about to feed her.

>Well, in an absolute sense no one, especially a baby, knows the future.

That's a different issue. The point is that you have to accept
the statement as true if you want to accept the "know" statement
as true. You can't say: The mother is not about to feed the baby,
but the baby knows that she is.

>IN any event, for a baby, I don't even think "belief" is necessarily
>a valid claim - it is more like "insticntually expects that the mother is
>about to feed her".

You're branching into separte issues. If you use "know" then you
require the presupposition. Whether babies are capable of
knowing is a different matter.

 >Having raised knowledge of the future, I will close with:
>I know that the sun will rise tomorrow.
>Is this a true or false statement?

Well, the sun will rise tomorrow, so at least the presupposition
is true. Whether you really believe it or not I can't say, but probably
yes, so I believe you.

>I know that someone will disagree with some element of my posting here.
>
>Is this a true or false statement?

Do you really need to ask? I bet you even knew who that
someone was... :)

co'o mi'e xorxes