Q-kau 2002: halfway towards a solution/resolution

["And Rosta" <a.rosta@ntlworld.com>]

The goals of our recurrent Q-kau debates are these:

1. to find a logical form to express what is or can be expressed in
English and other languages by (so-called) interrogative constructions

2. to find a (logically) appropriate way to express such logical forms
in Lojban (or to find a robust way to rationalize current usage in
terms of such logical forms)


I have been thinking about (1) and have come to agree with Jorge and
pc that what is expressed in English by (so-called) interrogative constructions
can be rendered into logical form by a formula involving
the predicate "X is a proposition that is a completion of incomplete
proposition Y", where an incomplete proposition is something that
has the form of a proposition but contains unbound variables; a proposition
that completes an incomplete proposition is one that replaces unbound
variables by bound variables (bound by a quantifier or by coreference
relations).

I won't explain how I justify these conclusions, since I am only
agreeing with a position already espoused by Jorge and pc.

At any rate, I consider (1) to be now resolved, so the remaining issues
are:

(A) Ignoring current usage, what would be the best way to express in
Lojban an incomplete proposition and its unbound variables? My best
shot would be a du'u clause containing "tu'o da" for unbound variables.

(B) The method in current usage is to express the unbound variables
by a Q-word + kau, within a du'u clause (which expresses the predicate "is the
incomplete proposition P"). The only way I can rationalize this
is to propose a rule that says "_Q-word kau_ expresses an unbound variable".
The relationship between Q-word with kau and Q-word without kau would
then be a relatively idiomatic one, in that a sentence with Q-word without
kau would be an abbreviation of a more complex sentence in which the
Q-words are with kau. Is this sufficiently 'lojbanic'? If yes, then
current usage can be given the blessing of the gods of logic. If no, then
the devotees of the gods of logic will want to alter their usage in a
manner yet to be established.


--And.