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Re: [ontolog-forum] Laws: physical and social

To: ontolog-forum@xxxxxxxxxxxxxxxx
From: John F Sowa <sowa@xxxxxxxxxxx>
Date: Tue, 04 Jun 2013 00:58:55 -0400
Message-id: <51AD740F.6020701@xxxxxxxxxxx>
Ed, Jim, Doug, and Leo,    (01)

Every ontology has axioms, but many ontologies do not have
a category Proposition -- of which some important special cases
would be various kinds of laws, both natural and social.    (02)

> for a particular purpose, one can encode a great many 'facts', that
> are "taken to be true"for the purposes of reasoning with that ontology
> for that purpose.    (03)

> I like to reinforce Ed's point that the knowledge engineer is
> responsible for determining what are "laws of nature" and what
> is "plausible inference"    (04)

I agree with both of you on those issues, but that is not the point
that I was trying to address.    (05)

Quine, for example, restricts his logic to FOL.  His axioms state
propositions, but he does not allow variables to refer to propositions.
That option is important for many purposes, especially for reasoning
about human organizations and social interactions.    (06)

> Actually, predicting physical properties of materials from their crystal
> structure did not really become viable until the late 1990s...    (07)

I agree.  Physicists have been talking about the laws of nature
for many centuries.  They may find it useful to classify materials
as hard, soft, or fragile.  But they recognize that those terms are
*dependent* on more fundamental laws -- even though it can definitely
be a nontrivial exercise to define them in terms of those laws.    (08)

> You are now talking about Bayesian inferences, which is significantly
> different from "common logic"    (09)

The police don't use Bayesian inference when they give you a ticket
for a traffic violation.  In any case, the issue of where you put
propositions in an ontology is independent of what you do with them.    (010)

And for that matter, any version of logic, CL or not, can be used
to state the propositions used for induction, abduction, deduction
by any method of reasoning, including Bayesian, heuristics, etc.    (011)

> Drivers do veer across the centerline, and your 2013 Mercedes may
> be one of those that is engineered to take evasive action automatically
> when that happens...    (012)

> Ed, i guess that you see the danger as being people using rules
> outside of their scope of applicability (i.e., the context in which
> they are valid).  This suggests that the context for any set of
> rules should be specified, and that anyone intending to use such
> rules should verify that they are within a context in which the
> rules are defined to be valid.    (013)

Yes.  And that is why it's important to make laws a *category* in
the ontology.  If you do that, you can do metalevel reasoning about
them and examine the various contexts and circumstances.    (014)

> There are many techniques (including fuzzy reasoning) for coming up
> with answers, but one must always allow for, as one moves from
> a probabilistic answer to what happens in a specific case, the
> possibility of the probable answer not corresponding with reality.    (015)

This is more metalevel reasoning.  Every version of modal logic,
fuzzy logic, and probability can be recast as a metalevel method
that reasons *about* the laws.  To do that, you need to make laws
(or more generally *propositions*) a category in your ontology.
For a summary of the basic ideas, see    (016)

    Worlds, Models, and Descriptions    (017)

>> A game theoretic model of a social interaction
>> and an axiomatic model of a social interaction are
>> radically different models.  (The axiomatic model -- the
>> "ontology" -- is the primary subject of this forum.)    (018)

> I would not equate the axiomatic model with the ontology.  An
> ontology can model a game theoretic model.    (019)

I agree with Doug.  The axioms of any ontology can be used for many
different purposes.  The inferences for reasoning about hypothetical
events in game theory could use the same axioms and the same theorem
prover as they would for reasoning about an actual event.    (020)

> Actually, physical laws are not as straightforwardly characterizable as
> you think.    (021)

I never said that discovering and stating laws is easy.  I just said
the universe is governed by the laws of nature and that laws should be
a fundamental category in ontology.    (022)

But discovering the laws of nature, stating them, and using them
effectively is definitely nontrivial.    (023)

> There are arguments for using dispositions in fact to characterize laws.    (024)

I checked some of your references on the WWW to see what they said
about laws and dispositions:    (025)

 From http://plato.stanford.edu/entries/laws-of-nature/
> For example, it seems that, for there to be any interesting counterfactual
> truths, there must be at least one law of nature. Would an ordinary match
> in ordinary conditions light if struck? It seems it would, but only because
> we presume nature to be regular in certain ways. We think this counterfactual
> is true because we believe there are laws. Were there no laws, it would not be
> the case that, if the match were struck, it would light. As a result, it would
> also not be the case that the match was disposed to ignite, nor the case that
> striking the match would cause it to light.    (026)

This is the basic point that I was trying to make:  the existence
of a disposition depends on the existence of some law.    (027)

But the author, John W. Carroll, goes on to discuss many thorny
philosophical issues about *recognizing* and *stating* laws.
I certainly agree.  He also says that the notion of disposition
is often a shorter and simpler way to express the point without
requiring a complete analysis of all the laws and their interactions.
I also agree with that point.    (028)

The article on dispositions goes into much more detail about the
the context-dependent conditions that are extremely important and
extremely difficult to specify in any kind of general terms:    (029)

 From http://plato.stanford.edu/entries/dispositions/
> most conventional dispositional predicates—‘fragile’, ‘soluble’, ‘malleable’
> and the like—make no explicit reference to the stimulus conditions and
> manifestations for the properties they express and the assumption that
> we are nonetheless in a position to identify those stimulus conditions
> and manifestations is controversial...    (030)

This article should be required reading for anybody who thinks that
it is possible to formulate a general theory of nonmonotonic reasoning.    (031)

I haven't checked all your citations, but these two certainly do not
make the case that dispositions are more fundamental than laws.    (032)

My primary argument is that laws are fundamental -- for the natural
sciences, for the social sciences, and for everyday life.    (033)

Dispositions can be a useful heuristic (a convenient shorthand)
for properties such as fragility, which are difficult to specify
in terms of the more fundamental laws.    (034)

John    (035)

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