Subject: Re: [lojban] Bald men

From: John Cowan <[email-masked]>
Date: Wed, 31 Oct 2001 15:15:49 -0500 (EST)

James F. Carter scripsit:

> As pc points out, English speakers could interpret the sentence two ways:
> "each and every man doesn't have hair", or "it's not true that every man
> has hair". A logician would pick the first one, Lojban is a logical
> language, and the Lojban text is constructed accordingly.

This is about how logicians construe English, not what "ro nanmu na se kerfa"
means.

> > which prenexes as
> > naku ro da poi nanmu zo'u kerfa da
> 
> No, it doesn't. The author hoped for the second interpretation, but has
> failed to use De Morgan's rules when re-ordering a negated sentence:

DeMorgan doesn't apply. This is one of the things that we changed from
Loglan to Lojban. In Loglan, "no" was always at the beginning of the
sentence: no raba jia mrenu ga -hair (I forget the Loglan for hair).
Lojban moved it *syntactically* to just before the predicate, but
*semantically* it still negates the whole sentence as it stands,
without any DeMorgan.

The position of naku, OTOH, is the same semantically as it is
syntactically, and you have to use DeMorgan if you move a naku
past a quantifier or logical connective.

All this is laid out in the Codex Woldemar.

-- 
John Cowan http://www.ccil.org/~cowan [email-masked]
Please leave your values | Check your assumptions. In fact,
at the front desk. | check your assumptions at the door.
--sign in Paris hotel | --Miles Vorkosigan