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Re: more epistemic perversity



>>If George is
>>presumed to be telling the truth about his internal state then
>>John should be able to report this fact as "George knows X".
>
>Not if X is not true and John knows it.

But it should not matter what John knows.  The claim to be evaluated is
"George knows X", and the truth or falsity of that claim should stand on its
own.  It should not be based on something irrelevant, such as the person
who happens to say it.  If you see the statement "George knows X" written
on a wall, and have no idea who wrote it, the whether that person who wrote it
thought X was true is irrelevant.  More likely you as reader will evaluate
truth based on whether YOU consider X true, not on whether the speaker/writer
considers X true.  So now we have a sentence that has a different truth
value to George, an unknown speaker, and you the reader (3 different truth
values are possible of course if we go fuzzy), and this seems nonsensical
without EXPLICIT context as to the standard for truth of x2.  Your claim
thus seems justification that English "know" requires such a standard of
truth in order to evaluate the truth conditions of a statement.  It is not
merely sufficient to invoke the speaker as the standard because the speaker
is not always the standard - the listener might be, or George might be,
depending on the context.

>>But as I understand it, you would have John's opinion/presumption/knowledge
>>somehow enter into the definition of djuno,
>
>Not in the definition. It enters in how John uses {djuno}, yes.

This sounds like a usage issue then and not a definitional one.  Whether or not
John would use djuno if he disputes the truth of le se djuno is of course up
to John.  But if truth of x2 is critical and Sam reads the sentence
la djordj cu djuno X, Sam will not care what speaker John thought about the
truth ofx2, but will consider only what George and Sam evaluate as true
(unless perhaps John is some kind of authority, in which case the x4 would
vary on staements of djuno in order to invoke John).

>You used (du'u) in most other places that require a {du'u} clause.

I hoipefully used du'u in all such places that require a du'u.  But I also
tried to put an English word-equivalent for the x2 in every such place
sometimes in square brackets if it made the text flow better.  The one I felt
clearest for djuno was "fact" because I wanted most importantly to make
sure that people did not use djuno for "know how to" which is the most likely
error an English speaker would make.  I do not know any word that I could
have used as an equivalent for x2 that conveyed this and nothing else that
was irrelevant (factoid might imply uncertainty of truth, for example, but
also carries connotations of trivia, and of quantitative data point).

>> You have also largely based your case on arguments
>>asosciated with objective facts - things that indeed most people can agree
>are
>>true such as numbers of children and dates of armistices.
>
>Those are the clearest examples to show that "knows" has
>presupposition of truth. If it didn't, there would be no reason
>for it to fail where "is convinced" works well.

But the cases where know/djuno will be used for things that a speaker may not
consider true is for things where objective truth is not necessarily available.
All you have shown is that there are places where "is convinced" breaks down
as a trnaslation for djuno, just as your implication have shown that "know"
sometimes breaks down as a translation for djuno.  Both English words are
flawed as translations, for different reasons.  "know" is less often flawed
because the times when we would use "know" when the speaker knows/believes
otherwise are relatively rare.

>>BUt people use the word "know" for other things that are not OBJECTIVELY
>>knowable.
>--More--
>
>Of course they do. Just as people use the word "true" for many things
>that are not OBJECTIVELY knowable.

Like how many planets there are.  That number could change any day as a new one
 is discoverable at any time.  If my statement "John knows X" can become false
based on something that is doscovered after I am dead, then it is neither
my knowledge of truth nor John's consideration of truth that is important.
Thus it is false to say that the speaker's presumption of truth is relevant to
the truth value(and hence the definition) of djuno/know.  The speaker's
presumption is irrelevant if the speaker's presumption is considered false to
the listener, or to some future listener.

>No problem with that. If you believe that there is a God, then you
>might say:
>
>        la djan djuno le du'u la cev cu zasti
>        John knows that God exists.

But an atheist would say that my statement is false, and what >I< presumed
in saying it has no bearing on the truth of the statement.  At least if we
base djuno on English usage.

>No problem with that. If you believe that there is a God, then you
>might say:
>
>        la djan djuno le du'u la cev cu zasti
>        John knows that God exists.
>
>        la djak naldjuno le du'u la cev cu zasti
>        Jack doesn't know that God exists.
>
>But if you believe that God does not exist, then you would not
>say either of those, because both presuppose the existence of God.

But what does
la djef na djuno le du'u la cev cu zasti
mean - you seem to imply that it also presupposes the existence of God.
But the proper Lojbanic way to deny a ledu'u that we consider false in such
a statement is NOT with "na" on the bridi, but with na'i on the du'u clause.

>>the statement in terms of "believe" if indeed we ourselves do not share the
>>presumption of truth.
>
>Not just more likely. If you couch them in terms of "know" your audience
>will understand that you are commited to the belief yourself.

But such connotational implications are NOT the sort of thing we want to
transfer into Lojban.  If I want to inject MY beliefs into a
statement about George's knowledge, I should use the appropriate member of UI

>> This is not the case for "believe" or "be certain", where "how?"
>>or "why?" are not always meaningful.
>
>It seems to be meaningful for  "be certain".
>"How can you be so sure?" seems seems pretty natural.

And it is a perfectly acceptable answer to say "I just am."

At least for some things one can be certain about.

>>I can say
>>mi djuno le du'u so da cu plini le solri
>>and provided that no new planets are discovered during my life, this will
>be
>>true throughout my life after 4th grade when I first learned this factoid.
>
>Right. (But notice that "this will be true throughout my life" presupposes
>that truths have a temporal extension, which kind of defeats what you're
>trying to argue for.)

My knowledge does indeed have temporal extent.  But what I am arguing is that
what lojbab knows on February 18 1998 is  a specific set of facts, and that
set of facts that I know on that date is invariant with time which might
prove every one of those facts false in the year 2098.  And the set of facts
I know is not dependent on who talks about what facts I know, whether it
be you or Sherlock Holmes.  And it similar should not depend on who reads
statements about the set of facts that I know on this date when such
readers have differing knowledge at differing dates.  What I know today
doesn't change.  Whether I know it at some other time, is open to question.

> >But you are claiming that if by some chance after I die that a tenth
>>planet is discovered, that
>>la lojbab pu djuno le du'u so da cu plini le solri
>>
>>somehow becomes false
>
>It doesn't "become" false. We discover that it is false.
>We discover that you and everybody else were mistaken.
>It happens all the time.

But if the statement doesn't "become" false, then it was false all the time,
and thsu your presupposition of the truthof x2 is in the final analysis
quite irrelevant to the truth of the djuno bridi.  When we discover that
something is false, all earlier presuppositions become irrelevant, and hence
were not really part of the meaning of the word itself.

>>I submit that the meaning of
>>la lojbab pu djuno le du'u so da cu plini le solri
>>
>>should not change depending on externalities such as what some people
>>may possibly find out at some future time.
>
>Of course the meaning didn't change! Our perception of the
>world changed, so that the meaning no longer matches our
>perception.

If it happens after your death, then your perception of the world did
not change, but you are the speaker whose presupposition is supposedly
relevant to the truith of the djuno statement.

>Right. In English we would then say: "Lojbab thought that there were
>nine planets orbiting the sun". In Lojban: {la lojbab pu jinvi le du'u
>so da cu plini le solri}.

But Lojbab did not hold that as an opinion, because the number of
planets is not a matter of opinion (at least to most people).  If you are
going to play word games withthe gismu list definitions then you must
accept ALL the words.    The English definition of jinvi does not suggest that
you can use it for just any old justified belief, since I did not use those
words, but only for opinions, where "opinion" is defined using the typical
English usage.

(This is a strawman - I don't consider that jinvi is necessarily confined only
to English opinion subject mnatters any more than I consider djuno is confined
to speaker-believed truths.  But it seems the logical follow-on to your
analysis).

lojbab

PS I am getting a raft of error messages suggesting that the UK people including
And are not necessarily getting list traffic right now, and the message is
different in that it doesn't imply a temporary delay.  No idea what the
situation is.

----
lojbab                                                lojbab@access.digex.net
Bob LeChevalier, President, The Logical Language Group, Inc.
2904 Beau Lane, Fairfax VA 22031-1303 USA                        703-385-0273
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