Re: Chief logician?

[Logical Language Group <lojbab>]

Yes, some of our analyses go against the grain of 'natural analogy', but so
far, for the most part, people haven't had much trouble.

For one thing, we have more explicitly defined negation as a predicate
negation that has full sentence scope, whereas natlang negation tends to
only have scope over 'the rest of the sentence' following the negation.
We define our negation as being immediately exportable to the prenex by
definition without change inquantifiers.  In my own usage, therefore, when
I rarely have to resort to quantified variables, I just leave the negation
in the prenex and do not use the 'short forms' of natlangs where the
variables are not explicitly quantified.  I find this form easier to 
understand, almost error-free in manipulation, and the circumstances where
I have been required to use it rare enough that Zipfean shortening doesn't
seem to enter in.

(We do have a natlang style negation form, but it isn't much used except in
translation.)

The easiest way to exemplify our variuos forms of negation is to refer you
to John Cowan's negation paper on ftp.cs.yale.edu pub/lojban/draft/refgrammar
At last report there was an error in one section (a DeMorgan expansion)
that might not have been caught, but it has lots of deatails of the various
forms of negation.

If I recall the discussion, the two more important kinds of negation are
defined by reference to a classic (I think Aristotle) 'box' diagram, where
contradictory negation is expressed by moving diagonally across the box, and
contrary negation by moving horizontally (ort is it vertically and horizontally
or ...).

I am not walking to the store

could mean
1) simply that it is false that I am walking to the store
2) that I am driving or running to the store

1) is contradictory negation
2) is contrary negation


Metalinguistic negation deals with things like
Have you stopped beating you wife?
when you haven't started  - it says that there is some hidden assumption that
is incorrect that makes the sentence not only false but meaningless from a
truth-functional point of view.

Contrary/scalar negation works very well on arguments:
I don't have 3 children (I have 2 or 4) is expressed in Lojban better
by nbenegating the argumetn "3 children".

Metsalinguistic negation crops up in a variety of ways.  Grammatically in 
Lojban it is an attitudinal (actually a discursive - but same grammar).
Contrary negation can be applied to arguments, can be applied to predicate
words within a metaphor, or can be applied to an entire metaphor or
predicate 9and a few other things).  Contradictory negation only applies to
sentences, and all forms of contradictory negation of a sentence negate the
entire sentence (Modulo the special natlang scope form which is used to
exempt quantified variables in a 'natural way')


====

Abstract raising has reared its uglu head in so many ways in Loglan/Lojban
that I hesitate to try to cover all of them.  One is underlying the current
discussion on nitcu/need.  Do you need an object, or do you need a state/event
involving that object?

Causality, is it 'guns' that kill (dead-cause) people, 'people' that kill
people, or 'people shooting guns' that kill people.  The first two are 
probably raisings of the third.  Most Lojban causality is now expressed
as 'event causes event' rather than 'object causes event' or 'object causes
object' or 'event causes object'.  But we have a form, now commonly used that
recognizes that we aren't always sure exactly what the event is, or how to
express it (or simply that it doesn't matter), so we can explicitly raise
the argument from abstract to object with a marked form.

e.g.
my work is done
le nu mi gunka cu mulno (lojban)
lepo mi turka ga kapli (TLI)
 and not
*lemi gunka cu mulno
?lemi turka ga kapli

but Lojban allows
tu'a mi mulno
raise I am-done
"I'm done."

which if the L1 place styruture is correct
"mi kapli" should never be said, unless perhaps at one's point of death
if you want to view yourself as an event.

We had to go through all of the place structures and decide which of them
took events as a norm, while which took objects (there are circumstances
where cossover is permitted and works without marking though), and in some
cases mosdify place structures to eliminate raising.  TLI Loglan words
that have hidden raising are most evident in predicates where there is
an abstraction in one argument, and a concrete (often an agent) in another
argument, such that the concrete is ALWAYS found as a place in the
abstraction.  This is not always 'bad', but we have found it worthwhile to
know exactly where it occurs, because logical errors seem to explode out of
such constructions.  (For one thing, quantified variables inside an
abstraction do not necessarily export to the sentence level.  But if the
two levels are muddled, you can get errors in scope.)

====
Oh, I failed to address one point under 'negation' - termionology.  We much
prefer to use 'real' definitions of terms rather than jargon definitiuons.
Only to a logician does 'negation' apply only to propositional forms.  English
words have English meanings, and most people think of 'negation' as being
tied to the meaning of "not" in a wide variety of usages.

You can control discussions by insisting on narrow meanings for words, but 
then you find that the results of the discussion do not have wide applicability.
WE chose instead to bite the bullet and tackle the fuzzier issues of negation
along with the purely propositional ones, because then people know how to
handle the concept "not" even when it is not purely a propositional usage.

lojbab