From: Kwok Chi Wing <chiwingkwok@cuhk.hk>
Subject: Re: Logic
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Date: Mon, 14 Dec 1992 05:50:39 GMT

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>From: gcf@panix.com (Gordon Fitch)
>Newsgroups:
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>Subject: Re: Logic
>Message-ID: <1992Dec9.220740.28830@panix.com>
>Date: 9 Dec 92 22:07:40 GMT
>References: <1992Dec8.073144.27250@genie.slhs.udel.edu> 
><1992Dec8.195638.21009@panix.com> <sd9q1k+@lynx.unm.edu>
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>gcf@panix.com (Gordon Fitch) writes:
>| >| }Logic is _not_ language?  Can you give me an example of 
>| >| }non-linguistic logic?  No words, numbers, ideograms,
>| >| }syntax?  What happened to the _logos_?
>
>Tim Starr:
>| >| Thought.
>
>gf:
>| >I want an
>| >example of logic which is non-linguistic.  By "language"
>| >I mean an arbitary system of symbols (usually words, but
>| >sometimes ideograms or other symbols) which are combined
>| >according to some set of rules (a syntax).  By my lights,
>| >logic is a language, but one whose symbols and rules are 
>| >more restricted than those of a natural language so that
>| >its productions will be more predictable.
>
>lgorbet@carina.unm.edu (Larry P Gorbet ANTHROPOLOGY) writes:
>| I think you are missing the point.  I would challenge you to give an
>| example of logic that *is* linguistic.  You seem to be confusing a
>| *representation* of logic with the logic itself.  Would you say
>| that physics is linguistic as well?  All of science?  All knowledge?
>
>It seems to me that the extant theories of physics consist
>of language, and that this is true of all of science.  But
>I could be wrong.  Non-linguistic forms of knowledge --
>modelings of the world -- are certainly possible; for instance,
>a map of New Jersey.  Or better, an aerial photograph.  But
>I've never seen a non-linguistic _theory_, as it happens.  
>There was Spencer-Brown's _Laws_of_Form_, but he needed to 
>surround his stuff with words, and I was never sure it all 
>wasn't a hoax anyway.
>
>But science aside, logic seems to me to be purely linguistic.
>I partly defined "language" above -- I left semantic considera-
>tions out, because I'm not sure that it's necessary to to
>specify that a statement mean something, or attempt to mean
>something, although "meaning something" wouldn't disqualify
>logic.
>
>Now, if I make up statements or propositions in logic, whether 
>I use the alphabet ("Socrates", "is", "therefore", ...) or ("p", 
>"=", "~", ...) or some other set of symbols, and constrain their 
>combination by a system of rules, it seems to me that what I 
>have done is to use language in a particularly rigorous form -- 
>but it's still language, and has the same problems other forms 
>of language have in representing the world, to wit, there is no 
>guarantee that every phenomenon will map to a symbol or 
>combination of symbols, and there is no guarantee that the rules 
>-- if there are rules -- for the world's combining of phenomena 
>will map to the language's rules for combining symbols.
>
>The original discussion arose out of my doubt that logic could 
>be said to produce truth about the world (unless it was 
>accompanied by religious faith in its operation.)  I would say 
>there is no sure truth but one's immediate experience.
>
>| To paraphrase, can you give me an example of a physical phenomenon
which
>| is not linguistic?  "No words, numbers, ideograms..."  
>
>Almost all of them.  It starts raining or stops -- no 
>language needed, as far as I know.  There are also a great
>many mental phenomena which seem to be non-linguistic.
>
>|                                                        To show that
>| logic is linguistic in some non-trivial sense, it would be necessary
>| to discover and explicate the inner mental operations of logic.  Or,
>| rather, of logics, since it is certainly far far from self-evident
>| that logics are unique, even within our species.
>
>I think that to show that logic is linguistic, I need to say
>what I mean by linguistic in some way we and others will
>agree upon, and show that logic comes under that definition
>-- at least for all appearances thus far.  Which is what I
>thought I did above.  Perhaps someone could give a more 
>rigorous demonstration, though; I'm an amateur in these 
>areas.  I don't think the "inner mental operations" of 
>either language or logic need to be discovered or 
>explicated, although it would be nice if we could do so.
>-- 
>
> )*(    Gordon Fitch    )*(    gcf@panix.com    )*(
>( 1238 Blg. Grn. Sta.,  NY NY 10274 * 718.273.5556 )

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>From: grantm@comlab.ox.ac.uk (Grant Malcolm)
>Newsgroups:
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>Subject: Re: Logic
>Message-ID: <1992Dec10.125639.1207@client82.comlab.ox.ac.uk>
>Date: 10 Dec 92 12:56:39 GMT
>References: <1992Dec7.203013.19246@panix.com> 
><1992Dec8.073144.27250@genie.slhs.udel.edu>
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>gcf@panix.com (Gordon Fitch) writes:
>
>> I want an
>> example of logic which is non-linguistic.  By "language"
>> I mean an arbitary system of symbols (usually words, but
>> sometimes ideograms or other symbols) which are combined
>> according to some set of rules (a syntax).  By my lights,
>> logic is a language, but one whose symbols and rules are 
>> more restricted than those of a natural language so that
>> its productions will be more predictable.
>> 
>> There are many forms of thought which are not linguistic,
>> but logic isn't one of them, as far as I can see.  
>
>A *formal* logic (count noun) consists of a language, a collection of
>axioms, and a collection of rules of inference.  Not all the sentences
>of the language are theorems of the logic, only those that can be
>derived from the axioms via the rules of inference.  Formal logics
>were intended, at least when they began to be studied, to formalise
>logical thought.  `Logic' (non count noun) is used in a great variety
>of senses, usually denoting some abstract (and often informal) notion
>of correctness or even appropriateness: "I don't see the logic in your
>flaming the poor soul."
>
>An example of non-linguistic logic is the validity of the following
>inference:
>
>  All women are mammals;
>  Socrates is a woman:
>  therefore Socrates is a mammal.
>
>The logic that validates this inference is non-linguistic, since the
>above syllogism can be expressed in a variety of languages, including
>first order predicate calculus, Greek, French, ....
>
>  Alle vrouwen zijn zoogdieren;
>  Socrates is een vrouw:
>  dus is Socrates een zoogdier.
>
>-- Grant.

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>From: pcollac@pyrnova.mis.pyramid.com (Paul Collacchi)
>Newsgroups: talk.politics.theory,talk.philosophy.misc,sci.lang
>Subject: Re: Logic
>Message-ID: <184590@pyramid.pyramid.com>
>Date: 10 Dec 92 20:54:45 GMT
>References: <1992Dec7.203013.19246@panix.com> 
><1992Dec8.073144.27250@genie.slhs.udel.edu>
<1992Dec8.195638.21009@panix.com> 
><1992Dec9.063726.2236@genie.slhs.udel.edu>
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>In article <1992Dec9.063726.2236@genie.slhs.udel.edu>,
>starr@genie.slhs.udel.edu (Tim Starr) writes:
>|> In article <1992Dec8.195638.21009@panix.com> gcf@panix.com (Gordon
>Fitch) writes:
>|> }| }Logic is _not_ language?  Can you give me an example of 
>|> }| }non-linguistic logic?  No words, numbers, ideograms,
>|> }| }syntax?  What happened to the _logos_?
>|> }
>
>Yes.  The Zen koan system is essentially such a system.  Also, 
>the Buddha's last and most powerful transimissions were alleged
>to have been given in silence.
>|> 
>|> I want an
>|> }example of logic which is non-linguistic.  By "language"
>|> }I mean an arbitary system of symbols (usually words, but
>|> }sometimes ideograms or other symbols) which are combined
>|> }according to some set of rules (a syntax).  By my lights,
>|> }logic is a language, but one whose symbols and rules are 
>|> }more restricted than those of a natural language so that
>|> }its productions will be more predictable.
>|> 
>
>Basically, "mysticism", not to be confused with either religion or
>occultism, is composed of truth seekers who were forced to abandoned
>'impure' epistemological methods, like thinking and sensing.  
>Needless to say language is abandoned, and then brought back in
>proper relationship -- as a tool for rendering, where possible,
>perceived truth.
>
>Logicians have a tendency to get it backwards, they get stuck on the
>language and think that by dicking around with language they can
>"discover" truth and add to their own synthetic knowledge base.
>
>In my opinion it just doesn't work that way.  Instead, one sees the
>truth, from time to time, or one simply knows it, and then one attempts
>to render or communicate it.  But no receiver can "get it" from 
>the communication.  The receiver can only see the truth himself and then
>know that a particular rendering was associated to that specific truth.
>
>In the koan system, a moment's revelation is called "satori."  The koan
>is the rendering.  It is not meant to convey truth, but merely to probe
>the listener to see if he has gotten it or not.  It is a sign-post.
>
>Paul Collacchi
Subject: Re: Logic
From:  Kwok Chi Wing  (The Chinese University of Hong Kong)
Email address:  chiwingkwok@cuhk.hk


"What logic is" is an ambiguous question.  We should try to clarify it
before we can really give the answer.  Some people who ask this question
may expect the answer tell us what "logic" refers to; some may expect we
will say something about the intension (i.e. meaning) of "logic".

Here, we will try to discuss the first one.

The term "logic", in our context, refers to a field of knowledge.  What
does this field of knowledge concern ?  Many may answer in this way: it
is a subject which investigates the underlying rule of thinking.  It is
even tempted to assert that (in fact, many philosophers did, such as
Kant) logic gives insight into the structure of our mind.  

However, after a careful examination, one can find out that all the
statements (or, to be more precise, propositions) in logic are analytic,
i.e. we need not examine the real world before we can decide whether such
statements is true.  It has no empirical content and hence it cannot tell
us anything about the structure of our mind.

Then, what job does logic actually do ?  Logic is a subject which
investigates logical concepts.  By the term "investigate", I mean
"analysis".  Loosely speaking, logical concepts includes logical
conectives (e.g. "and", "or", "if...then...", "not", "neither...or...",
"unless", ...etc.) and also some of the concepts which frequently appear
and is key to determine the truth value of our statements (such as "for
all", "there is some", "there is at least twelve", "there is not", "it is
possible", "it is not possible",...), some basic concepts (such as
"true/false", "valid/invalid argument"...).  What a logicist does is to
clarify all these concepts and find out the relation between them.  As an
example, a truth table for "and" is a clean way to define the concept
"and" in term of the concept "truth value".

How can logic help us in thinking, if logic is really something like this
?  Clear thinking requires clear concepts.  Logic helps us in this way ! 
In fact, saying that logic gives us rule of thinking sometimes may be
misleading (especially when we want to understand the nature of the
subject; note that I only say that it is misleading, not say that it is
wrong).

What is my point ?  My point is that logic, in this sense, is linguistic
(of couse, the term "linguistic" is not quite well-defined).
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