Re: Re Cowan#2 lo, da poi

[Logical Language Group <lojbab>]

mi pu cusku di'e

> The "official" line on "lo" and "da poi" has always been that they don't
> mean the same thing, because "lo -nonexistent" could be valid, whereas
> "da poi -nonexistent" was self-contradictory, as "da" can be glossed
> "there exists an X".  I now believe this to have been a mistake: "lo"
> under current definitions is the equivalent of "da poi", simply syntactic
> sugar.  However, I am going to propose a small change in interpretation
> that will give it added value.

la djer. cusku di'e

> There might be other contexts besides negation where "da poi" as a
> direct substitution for "lo" would yield unexpected results.
> For example:
> 
> 1). lo ro tanxe cu ckaji lo xa sefta
>  All the real boxes have the property of six surfaces. (The boxes exist)
> 
> 2). da poi ro tanxe cu ckaji lo xa sefta
>  Something which is all boxes has the propery of six surfaces.

Note the phrase "syntactic sugar".  I did not mean that "lo" can be
substituted for "da poi" or vice versa, simply that the meaning of one
construct is defined in terms of the other.  In particular, "lo" takes
a selbri, whereas "da poi" takes a full bridi; furthermore (as you rightly
indicate) "lo" can have an inner quantifier, which makes an incidental
assertion about the cardinality of the description (number of members in
the set), as all LE/LA cmavo can; to express the same thing with "da poi"
requires circumlocution.

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