[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [lojban] {zo'e} as close-scope existentially quantified plural variable
I think there may be other possibilities. For example, {lo broda} may return a bunch, all of the subbunches in a partition of which broda in sense i.
So, the glorked (whence this word btw) have to be unicorns in some world. Why not in this one? That is my intention; otherwise I have a mess of problems about cross- worlds identity and the meaning of predication (which, partly, I suppose, is why you want to add {ka'e}).
Now, depending on the context, {lo pavelseljirna cu lazni} may or may not take us to a world where unicorns exist, but the point is that it does not have to; we can and do fold nonexistent unicorns -- items in the extension of {pavelsejirna} -- into our current domain of discourse, which depends on what we say, not on the facts.
Sent from my iPad
On Oct 20, 2011, at 20:10, Martin Bays <mbays@sdf.org> wrote:
> * Thursday, 2011-10-20 at 12:26 -0400 - John E. Clifford <kali9putra@yahoo.com>:
>
>> Now I am mor con used than before. Why is there only one bunch off
>> people living in glass houses and why must they all exist at one time
>> / in one world, and why can't they? I am unclear what restrictions
>> you are placing on worlds an domains. I am also unclear as to what
>> you think the logical form of "People who live in glass houses should
>> install proper insulation" is.
>
> Hmm. Probably I'm making some assumption which you're not, leading to
> confusion. But I'm not sure what that assumption might be. So let me
> just express again the issue in different words:
>
> Ignoring all the more subtle issues we've been discussing, there are two
> basic possible bunch-theoretic meanings for {lo}. When applied to
> a unary predicate P, it either
> (i) returns a bunch X such that P(X)
> or (ii) returns a bunch X such that for every atom x below X, P(x).
>
> ("atom x below X" could also be written "individual x in the bunch X";
> I'll continue to use the 'atom' terminology because I think it best
> indicates that individuals aren't disjoint from bunches - individuals
> are just "singleton" bunches. I'll use the notation "x <= X" to mean
> that x is an atom below X (so lower case variables are "singular
> variables", i.e. are variables on the atoms sort))
>
> If we write {lo pavyseljirna cu lazni} to mean "unicorns are lazy"
> (which I believe is true - who ever heard of a pack-unicorn or
> a unicorn-plough?), the unary predicate in question is probably
> (slightly) more precisely expressed by {ka'e pavyseljirna}, and is:
>
> U(X) <=> "there exists a world w such that pavyseljirna(X) in w".
>
> Under (i) we get:
>
> {lo pavyseljirna cu lazni}
> -> GL X:U(X). lazni(X)
> == "for a glorked bunch X such that U(X) holds, lazni(X) holds"
>
> whereas under (ii) we get:
>
> {lo pavyseljirna cu lazni}
> -> GL X:(FA x <= X. U(x)). lazni(X)
> == "for a glorked bunch X such that U(x) holds for every atom
> x below X, lazni(X) holds" .
>
> Substituting in the definition of U and using distributivity, under (i) we get:
>
> GL X:(EX w. pavyseljirna_w(X)). lazni(X)
> == GL X:(EX w. FA x <= X. pavyseljirna_w(x)). lazni(X)
> == "for a glorked bunch X such that for some world every atom below
> X is a unicorn, X is lazy"
>
> while under (ii) we get:
>
> GL X:(FA x <= X. EX w. pavyseljirna_w(x)). lazni(X)
> == "for a glorked X such that for every atom below X there is
> a world in which it is a unicorn, X is lazy" .
>
> So the (ii) case is the one we want, if we want to get at the sense of
> the english "unicorns are lazy".
>
> Did that make any more sense?
>
> Martin
>
>> On Oct 19, 2011, at 22:41, Martin Bays <mbays@sdf.org> wrote:
>>
>>> * Wednesday, 2011-10-19 at 19:11 -0700 - John E Clifford <kali9putra@yahoo.com>:
>>>
>>>> U\I'm not going to worry about {loi} etc. until I am sutre about {lo} and then
>>>> see what is lefyt over that needs dealing with. {lo cipnrdodo) refers
>>>> to all the dodos there ever were (suppose that is right for this
>>>> context), all of which are thus in the domain of discourse and also in
>>>> the extension of {cipnrdodo}. What problem are you having; I just
>>>> don't see it?
>>>
>>> Hmm. So you'd want every dodo which ever lived to now cipnrdodo - even
>>> if it doesn't zasti, nevermind jmive?
>>>
>>> That might work for some cases, but what if we want to say "people in
>>> glass houses should install proper insulation"? Even if the people in
>>> question (who mostly don't zasti in this possible world, nevermind now)
>>> were to ca ca'a prenu, they surely couldn't ca ca'a nenri su'o blaci
>>> zdani; nor is there any other world in which they all do.
>>>
>>> So the bunch of them doesn't satisfy {prenu gi'e nenri su'o blaci
>>> zdani} - since there's only one bunch, we would need that the bunch
>>> satisfies this in some given world. It doesn't.
>>>
>>> But each atom (person, in this case) in the bunch does satisfy {prenu
>>> gi'e nenri su'o blaci zdani}. So for {lo prenu poi nenri su'o blaci
>>> zdani} to get the bunch, we'd need the quantifier over worlds to go
>>> inside a quantifier over the bunch. The gadri seems the right place
>>> to specify this.
>>>
>>> Martin
>>>
>>>> ----- Original Message ----
>>>> From: Martin Bays <mbays@sdf.org>
>>>> To: lojban@googlegroups.com
>>>> Sent: Wed, October 19, 2011 1:44:49 PM
>>>> Subject: Re: [lojban] {zo'e} as close-scope existentially quantified plural
>>>> variable
>>>>
>>>> * Tuesday, 2011-10-18 at 01:44 -0400 - Martin Bays <mbays@sdf.org>:
>>>>
>>>>> * Tuesday, 2011-10-18 at 00:47 -0400 - Martin Bays <mbays@sdf.org>:
>>>>>
>>>>>> * Monday, 2011-10-17 at 19:46 -0700 - John E Clifford
>>>> <kali9putra@yahoo.com>:
>>>>>>> ----- Original Message ----
>>>>>>> From: Martin Bays <mbays@sdf.org>
>>>>>>>> Maybe I finally understand what you mean with your "kinds = maximal
>>>>>>>> bunches" idea. Let's see.
>>>>>>>>
>>>>>>>> I've been implicitly assuming that in {lo broda}, the tense inside the
>>>>>>>> description is by default copied from outside it. So {mi ca ca'a nelci
>>>>>>>> lo pavyseljirna} == {mi ca ca'a nelci lo ca ca'a pavyseljirna}, which is
>>>>>>>> false if there are no unicorns.
>>>>>>>
>>>>>>> I suppose the tense (if there is one) is as contextual as everything else
>>>>> about
>>>>>
>>>>>>> descriptions. The same as the bridi surely is a good guess in general, but
>>>>> may
>>>>>
>>>>>>> be obviously wrong in other circumstances. For example, in generalities,
>>>>> the
>>>>>
>>>>>>> tense (if that is the right notion) is probably past, present, future and
>>>>>>> possible.
>>>>>>
>>>>>> Right, so I think I do understand you.
>>>>>>
>>>>>> Does this work?
>>>>>
>>>>> But there's something of a problem: if the plural referent of {lo broda}
>>>>> is meant to satisfy broda, what tense can give us e.g. all dodos ever?
>>>>> The plural referent of {lo pu cipnrdodo} must satisfy {pu cipnrdodo},
>>>>> i.e. must have satisfied {cipnrdodo} at some point in the past. But that
>>>>> means we're picking up some dodos all of which existed at the same time.
>>>>>
>>>>> So it seems we'd have to have the rule be that {ro lo broda cu broda},
>>>>> rather than {lo broda cu broda}, for this to work.
>>>>
>>>> ...and then it might make sense to have {loi broda} be the same as {lo},
>>>> except that the plural referent is required to broda (rather than the
>>>> atoms below it brodaing). So while {lo pu cipnrdodo} could get the bunch
>>>> (aka plurality) of all dodos ever, {loi pu cipnrdodo} would have to get
>>>> a bunch all of which cipnrdodod at the same past time (which might imply
>>>> that they were all alive at the same time, or if dead at least not too
>>>> far decomposed...).
>>>>
>>>> So this contains some of the essence of the historical meaning of {loi},
>>>> and is usefully distinct from (the understanding under discussion of)
>>>> {lo}.
>>>>
>>>> Martin
>>>>
>>>> --
>>>> You received this message because you are subscribed to the Google Groups "lojban" group.
>>>> To post to this group, send email to lojban@googlegroups.com.
>>>> To unsubscribe from this group, send email to lojban+unsubscribe@googlegroups.com.
>>>> For more options, visit this group at http://groups.google.com/group/lojban?hl=en.
>>
>> --
>> You received this message because you are subscribed to the Google Groups "lojban" group.
>> To post to this group, send email to lojban@googlegroups.com.
>> To unsubscribe from this group, send email to lojban+unsubscribe@googlegroups.com.
>> For more options, visit this group at http://groups.google.com/group/lojban?hl=en.
>>
--
You received this message because you are subscribed to the Google Groups "lojban" group.
To post to this group, send email to lojban@googlegroups.com.
To unsubscribe from this group, send email to lojban+unsubscribe@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/lojban?hl=en.