Re: TECH: more thoughts on zi'o

[Logical Language Group <lojbab@ACCESS.DIGEX.NET>]

mi'e .djan. .i la .art. protin. cusku di'e

> I accept "P(a,b,c,d,zi'o)" as "there is no e such that P(a,b,c,d,e)"
> provided that zi'o is always required to be stated, never implied.

No, that's not what it means.  P(a,b,c,d,zi'o) is a four-place predicate,
such that P(a,b,c,d,e) implies P(a,b,c,d,zi'o), but not vice versa.
We can infer from "mi klama le zarci" that "mi klama le zarci zi'o zi'o zi'o",
but the relationships are not the same:  the first case asserts "I go
to the store from somewhere with-route something with-means something"
whereas the second asserts "I go to the store", period.  I do >not< assert
the existence of origin, route, or destination -- which is not the same
as denying they exist.

> The construct "P(a,b,c,d,...)" says nothing about the existance or
> relevance of e unless the the relation P is such that e is guarenteed
> to exist, as is the case with klama.  Even when e is guarenteed to
> exist, when e is unspecified nothing more is implied about it.
> The construct "not P(a,b,c,d,...)" says to me that there exists
> a value of e such that "not P(a,b,c,d,e)" is true.  This is a much
> weaker claim than there is no e such that "P(a,b,c,d,e)" is true.
> The stronger claim is represented as "P(a,b,c,d,zi'o)" which is
> where this paragraph began.

No, the claim with "zi'o" is the weaker claim.  To assert that there is
no such e, you assert "P(a,b,c,d,noda)" which is the same as "~(Ex)
 P(a,b,c,d,x)"

> (Tell me again John why the loglan predicate "bluer-than" is
> impossible to use with negation.)

It's not impossible per se, it just makes the reading of "blanu(a,...)" as
"a is blue" untenable, because "~blanu(a,...)" ends up meaning "it is false
that a is bluer than something" or "it is false that a is bluer than anything",
depending on whether the hearer infers an existentially or a universally
quantified value for the ellipsis.

Both of these can be refuted by particulars: on the existential reading,
"leaves are not blue" comes out false, because leaves are bluer than, say,
the sun; on the universal reading, "the sky is not blue" comes out true,
because the sky is not as blue as a standard-blue color chip.

You can't have it both ways.  Saying that something is not blue simply
cannot be construed as any sort of implicit comparison.
Remember that "not" here is always contradictory negation; I am not talking
about "non-blue".

Sidenote: somebody made the claim that "not", the computer operator, was
always close binding.  Well, that's true in C, but false in Algol 60,
where things like:

        a 'eq' b 'and' 'not' c 'eq' d

group as:

        (a 'eq' b) 'and' ('not' (c 'eq' d))

--
John Cowan              sharing account <lojbab@access.digex.net> for now
                e'osai ko sarji la lojban.