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Re: [ontolog-forum] {Disarmed} Re: OWL and lack of identifiers

To: patrick@xxxxxxxxxxx
Cc: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Pat Hayes <phayes@xxxxxxx>
Date: Sun, 29 Apr 2007 10:40:37 -0700
Message-id: <p06230936c25a795f87df@[192.168.1.9]>
(I will try to address the substantive points in what follows. This 
thread is rapidly becoming a cultural food-fight of no real interest. 
-Pat Hayes)    (01)

>>>>
>>>True enough but note that earlier in this thread there was the following
>>>exchange:
>>>
>>>Steve Newcomb:
>>>
>>>When it comes to a question that cannot have an objective answer
>>>
>>>Pat Hayes responding:
>>>
>>>But it can, both as a question in cultural sociology and as a
>>>question in semiotics. Believe it or not, people have thought about
>>>questions like this rather carefully, in many cultures.
>>>
>>>
>>>Even "consensus" doesn't equal "objective" answer.
>>>
>>>I have no difficulty with anyone claiming that their favorite ontology
>>>or method gives a more useful answer (by some scale) than another
>>>ontology or method.
>>>
>>>But, I do object to the notion that there are "objective" answers. (full
>>>stop)
>>
>>
>>I think you are reading more into that word than I do. Objective 
>>does not mean final, absolute, or permanent. It means concerned 
>>with facts rather than opinions. What this thread began with was 
>>the question of whether it was possible for there to be objective 
>>facts about logic, or whether in contrast any logic was culturally 
>>embedded and hence merely a collection of opinions or habits or 
>>perhaps cultural prejudices. And my point was simply that this 
>>second idea about logic is plain flat wrong, and (I suspect) arises 
>>from ignorance about the actual subject itself. What technical 
>>logic (aka 'mathematical logic' or 'formal logic' or simply these 
>>days 'modern logic') has developed is a collection of ideas and 
>>methods of analysis that amount to an *objective* theory of truth, 
>>and hence of the superstructure of ideas which rest on this notion 
>>of truth: entailment, validity, consistency, etc.. To call this 
>>'objective' is not to claim that it is a final, absolute truth 
>>which cannot be challenged. (Amusingly, most of my professional 
>>life has been spent challenging one part of it or another.) It is 
>>to say that the challenge must be more articulate and analytical 
>>than merely disparaging the entire subject as a cultural opinion, 
>>just one more subjective view among a multitude of equally mythical 
>>cultural positions vying validly for attention, and deserving of no 
>>special claim on our allegiance. That is a fundamental intellectual 
>>mistake, and ultimately an anti-intellectual and anti-scientific 
>>stance to adopt. It seems to go along with a view that Truth (note 
>>the use of the mystical Capital Letter) is something unattainable, 
>>beyond the lowly human realm, something transcendent, almost 
>>religious; so to claim to have a science of mathematics of Truth is 
>>ridiculous, and a sign of a limited cultural imagination. But this 
>>is just the other side of the same misunderstanding. We can, and 
>>do, have an objective theory of truth precisely because truth is 
>>not transcendent or unknowable or absolute. It is limited, mundane, 
>>and tied to human forms of expression, and we are often mistaken 
>>about it; but not about what it *is*.
>>
>I suspect we have started from different assumptions concerning "logic."    (02)

Possibly. One of the reasons for my rather acidic tone is that I get 
irritated by attacks on logic based on misunderstandings about it or 
ignorance of it. What I was referring to by this word is the general 
body of scholarship and results which is (rather loosely) referred to 
as 'logic' in the scientific/philosophical literature. This includes 
semantic theories of one kind or another, which is what I was 
referring to when I mentioned objective theories of truth.    (03)

>I would agree that it is possible to state "facts" about logic, such 
>as FOL, since it starts from a given set of fundamental propositions 
>and statements based on those propositions can be said to be 
>consistent with those beginning propositions. If you want to call 
>those "facts" I suppose you can use that term if you like but it 
>runs the danger of being confused with the more common use of the 
>terms "facts."    (04)

I was using the word in its ordinary sense. The logical sense is a 
fomalization (actually many formalizations) of the ordinary sense.    (05)

>That is to say that logical proofs are a means of demonstrating that 
>some conclusion is consistent with the fundamental propositions of 
>logic, for which no proof is offered.    (06)

No. That is a reasonable account of the process of using logic to 
demonstrate consistency of a theory (aka ontology), but the logic 
itself has no fundamental propositions. Well, to be picky, it has 
some. The fundamental propositions of FOL are that something exists, 
that there are no a priori restrictions on what must exist (other 
than the first supposition), and that the things that exist stand in 
relations to one another. That is all. It is very hard (for me) to 
even imagine what it could mean to claim that these are false.    (07)

>And I would agree that given the fundamental propositions, proofs 
>are not subject to the claim that they are in some way culturally 
>biased or even dependent upon culture.
>
>However, there is an intellectual sleight of hand in your first 
>paragraph that you repeat in your reply to Newcomb today that may 
>have been missed by some readers so I will try to tease it out from 
>your prose.
>
>Recall that we start from the premise that statements can be made 
>using a logic, such as FOL, that can be "proved" to be consistent 
>with its given premises. I don't think anyone seriously disagrees 
>with that statement. But note that all FOL can offer is that some 
>given statement is consistent with    (08)

Actually, follows from or entails. But whatever.    (09)

>the premises of FOL and whatever other premises you supply.    (010)

Of course. How could it be otherwise? But 'other premises you supply' 
is a huge category of possibilities. To argue that this somehow 
introduces a bias, you need to argue that there are some kinds of 
premis that cannot be encoded in FOL. (This claim isn't by any means 
obviously false, and people have of course claimed this in many 
forums.)    (011)

>But, then you make the curious statement: *It means concerned with 
>facts rather than opinions.*
>
>Then of course you go into the usual rant about "anti-intellectual 
>and anti-scientific, etc." which is meant to tar anyone who 
>disagrees with you with a variety of perjorative labels.    (012)

Hmm. Your use of the word 'usual' here suggests that you may have had 
this kind of discussion before on other occasions, am I right?    (013)

>But the critical move is the assumption that simply because given a 
>set of fundamental premises, anyone with training in formal logic 
>will agree that some statement or proof is consistent with the 
>requirements of FOL that extends beyond the confines of FOL to 
>include your *facts rather than opinions.*
>
>That is quite a jump and one often unseen by those who want logical 
>"proof" of whatever the contemporary bigotry is the coin of the 
>realm.    (014)

I note that 'bigotry' isn't exactly an objective term. If you think 
FOL is bigotry, you should try living in a fundamentalist state.    (015)

>Let me be clear: I carry no brief against formal logic and think 
>that it has been, is and will be incredibly useful both within and 
>without work on ontologies. But, that does not mean that formal 
>logic in any shape, form or fashion offers an *objective theory of 
>truth*. (note the lower case "t" in truth)    (016)

It does not mean that; but nevertheless, modern logical semantics (of 
which you seem to be completely unaware) *is* an objective theory of 
truth. Note, this is not to say that it is a theory which establishes 
the objective truth of truths: only that is is theory of what it is 
to be true, of the nature of truth; and it is a theory which is not 
(in any way I have ever seen analyzed) culturally biassed.    (017)

>>>I am reminded of a PBS special on the mind that reported the story of an
>>>English patient who as the result of a brain fever had a time window of
>>>about 30 seconds. He kept a journal in which he repeatedly wrote: "Now I
>>>am awake." When questioned about the entries prior to the one he had
>>>just written, he would vehemently deny authorship of the prior entries.
>>>
>>>There have been no shortages of "Now [we are] awake." moments in human
>>>history. I see no reason to give current claims any more credit than we
>>>are generally inclined to give prior claims of the same nature.
>>
>>
>>So is your point that we should ignore all of science and 
>>philosophy because it will eventually be replaced by something 
>>else? That seems like a recipe for always doing nothing.
>>
>No, my point was that gradiose claims of being *the answer,* whether 
>from formal logic or any other methodology should be ignored.    (018)

I havn't suggested that logic is "the answer". I have no idea what 
this could mean, in part because I don't know what the question is.    (019)

>Marvin Minsky, who is still considered by many as one of the leading 
>supporters of the strong AI position, certainly doesn't view logic 
>as the only methodology to be used in a successful AI system.    (020)

I am vividly aware of this. I have argued the point with Marvin on 
several occasions. It turns out we largely agree. (FWIW, Marvin is 
much more accommodating about the use of logic nowadays than he used 
to be. Many of the old anti-logical firebrands, including Doug Lenat, 
have seen the error of their old ways. )    (021)

I also don't think  that FOL is 'the answer' for AI knowledge 
representation (a point where I disagree with the other leading 
supporter of strong AI, John McCarthy). On the other hand, I do get 
rather exasperated when people (and Marvin was once one of them) 
suggest as an alternative something that pretty obviously is merely a 
subset of logic written in a different notation, which has happened 
now quite often.    (022)

By the way, the literature of 'Topic Maps' seems to include a kind of 
vague groping towards a semantic theory, but it has not yet reached 
the level of technical sophistication that logical semantics reached 
in the mid-1960s. Sometimes it is a very good idea to not try to 
re-invent the wheel, particularly if you don't know any wheelwrights.    (023)

>You may find the podcasts, "It's 2001, Where is Hal?" amusing:
>
>http://ddj.com/dept/ai/197700454
>http://ddj.com/dept/ai/197700449
>http://ddj.com/dept/ai/197700447
>
>
>And no, I haven't ever said that we should ignore all of science and 
>philosophy.
>
>But then cherry picking science and philosophy to support some 
>highly suspect notion of "facts"    (024)

Virtually all of science is based on the distinction between 
objective facts and subjective opinions. The very idea of 'science' 
is based on a methodology for clarifying and sharpening that 
distinction, often called the scientific method. I'm not 
cherrypicking here.    (025)

>isnt' what I consider to be following science and philosophy. I seem 
>to remember most of the 20th century being concerned with debates in 
>philosophy that you want to settle with your "facts vs. opinions" 
>position.    (026)

Thats not what I remember. Which debates are you referring to, which 
depended on arguments about facts being indistinguishable from 
opinions? Which branch of philosophy? (There may have been some such 
debates in postmodernist French philosophy, come to think of it.)    (027)

>>>Certainly we should argue for whatever answer we think is the best one
>>>but my only caution is to avoid wrapping our answer (it is never someone
>>>else's) in the mantle of being an "objective" answer. That cuts off any
>>>debate and automatically disenfranchises any contrary viewpoint.
>>
>>
>>Nonsense. Most useful debate is about objective claims. And most 
>>useful debate is not merely the pitting of contrary viewpoints 
>>against one another, but arises when people try to understand the 
>>other position: which often requires a lot of mutual education.
>>
>So you think berately people on this list for being 
>"anti-intellectual and anti-scientific" is a form of useful debate?    (028)

I did say 'ultimately', and I was talking of positions rather than 
people. My point was that to describe the best theory of truth that 
we so far have, and one that is widely used and widely found useful, 
even essential, throughout linguistics and much technical philosophy, 
as a mere cultural bias, a form of bigotry, and so forth, is 
anti-intellectual. And claiming that there are no objective facts is 
anti-intellectual. Yes, I do believe that. Although 
'anti-intellectual' might be giving it too much weight. I actually 
think it is kind of pathetic, like complaining about machine-made 
furniture which is better than hand-made could possibly be.    (029)

>Hmmmm, I suppose we must disagree about "useful debate" as much as 
>we do about your claims of being "objective."
>
>I don't think recognizing logic as being concerned with formal 
>consistency with a fundamental set of propositions in any way 
>diminishes the importance of logic in the many realms where it is 
>used.    (030)

You clearly do not understand logical semantics. Which was my main 
point. By all means criticize it: but please do so from a position of 
comprehension, rather than ignorance.    (031)

>Or to put it another way, logic is *not* concerned with "objective" 
>truths, facts, etc.    (032)

Yes, it is. It doesn't *establish* their truth, of course; but is 
*concerned* with it; and the truth with which it is concerned is 
objective truth: correspondence to a world. Logic is not purely about 
formal derivations or formal consistency. I'm not going to argue with 
you any more about this. You are simply wrong.    (033)

>With the appropriate starting premises, any statement that is not 
>itself inconsistent    (034)

Actually, not consistent.    (035)

>with the fundamental premises of FOL can be "proven."    (036)

It can be proven, no need for the scare quotes. Well, unless you are 
using a paraconsistent logic, that is.    (037)

>That doesn't make it "objective" or even true.    (038)

I think you are referring to the fact that a logical inconsistency 
logically entails anything. Of course that does not make the 
inconsistency true, and nobody ever said it did. You are completely 
misunderstanding me.    (039)

>Hope you are having a great weekend!    (040)

Likewise (really :-)    (041)

Pat    (042)

>
>Patrick
>
>--
>Patrick Durusau
>Patrick@xxxxxxxxxxx
>Chair, V1 - Text Processing: Office and Publishing Systems Interface
>Co-Editor, ISO 13250, Topic Maps -- Reference Model
>Member, Text Encoding Initiative Board of Directors, 2003-2005
>
>Topic Maps: Human, not artificial, intelligence at work!    (043)


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