Re: fuzzy lojban

[sbelknap@uic.edu (Steven M. Belknap)]

lojbab-

I'm working on my "requirements for fuzzy logic" Thanks for your reply. It
may actually be an advantage that some of this stuff has not been fully
considered prior to this fuzzy issue being raised.

>>1. Where exactly does it say in the BNF, YACC, Refgrammer, or cmavo
>>definitions that crisp logic is being used? I don't see it.

>I doubt that you will find it.  I don't think it ever entered my mind to
>specify it.

OK, thats reassuring. I was concerned I was missing something. The
situation is much clearer to me now. There is fuzzy light at the end of the
fuzzy tunnel!

>
>>Other than some
>>vague statement that lojban is based on predicate logic, I don't see
>>*anywhere* where the set membership and logic functions are specified.
>
>What do you mean by "set membership" and "logic functions"?

I will post something to the lojban list soon regarding this.

>Set membership is expressed using the predicate cmima, which is not defined
>whether it is "crisp" or "fuzzy" membership, and the non-logical connective
>ce and ce'o, and the set-converters lu'i and , I think vu'i (for ordered
>sets), the cardinal "mei" which has a place for set members to be enumerated,
>and "me/ME".


>>3. How do we know that lojban logic isn't already fuzzy?
>>
>
>We probably don't, but haven't considered it (unless pc has).

I want to emphasize that I am not intent on adding my personal cmavo to the
language. If fuzziness is there, all we need do is discover it. So far, it
doesn't appear there is enough fuzziness, but this may be because some
basic implicit assumptions were made which can now be made explicit, then
perhaps modified/generalized to include fuzziness. I will try to address
this in my "requirements" posting, which I'm working on.

>>5. Would there be any obvious problem to using Max, Min, etc as the logical
>>operators for the default set membership function of lojban? (they would
>>work in the expected way for both fuzzy and crisp logic)

I am using the standard mathematical definitions of Max & Min. I will cover
this in my "requirements" post.

>>The available material appears to be agnostic as to the fuzziness or
>>crispness of lojban grammer. The conn.txt paper could be interpreted as
>>specifying crisp membership functions in its description of truth tables,
>>etc.
>
>That would certainly have been my assumption, never having seen a truth table
>built around anything other than two-valued logic.  But I would presume
>that if the predicates being connected were other-than-two-valued, that the
>connectives would operate on them in some appropriate manner.  If you want
>to specify such a manner, we need to see the requirements.

Understood.

>
>What Cowan has been calling the "logic paper" is not conn.txt, which is the
>"connective paper".  The "logic paper" is
>nobody.txt and describes aspects of quantificational logic, and who knows what
>else, since I haven't seen it %^).
>

I haven't read the new version of the nobody paper either. I'll reread that
tonight. Some of the material in the negation paper has been moved to the
connective paper, so I would call the connective paper the "logic paper".
Whatever. I'm glad that John Cowan added chapter numbers. Sometimes you
guys throw around names that are more <la>-like than <lo>-like :-)

>I want to reiterate that we have NEVER seen from you a statement of what
>you perceive to be the requirtements for coverage of fuzziness in Lojban.
>You persist in trying to associate design features with what are to everyone
>else, rather nebulously defined concepts.

Its not that simple. Fuzzy logic and fuzzy sets is a big field. In order to
understand what aspects of fuzziness are most appropriate to lojban, I have
felt a need to understand two things:

1. Which aspects of fuzzy logic/sets are relevant to language.
2. Which aspects of fuzziness are already in lojban.

I'm sorry if this is frustrating you, but I don't see any other way to
proceed. I am working as fast as possible on my "requirements".

>To get any official recgnition
>of fuzziness, we need to know what we are trying to do, and I personally feel
>that it would be better to let US try to map requirements to whether and how
> they are covered in the language, once we understand what it is you are trying
>for ("us" being Cowan, pc, myself, and possibly Nick Nicholas now that he
>again exists, assuming he has some knowledge of fuzzy logic - he does have
>sufficient knowledge of the language to be consulted if he knows the concepts.)
>We don't know the problem, and hence cannot comment on any solutions.

I agree.

kamkuspe stivn


Steven M. Belknap, M.D.
Assistant Professor of Clinical Pharmacology and Medicine
University of Illinois College of Medicine at Peoria

email: sbelknap@uic.edu
Voice: 309/671-3403
Fax:   309/671-8413