Re: [ontolog-forum] intangibles (was RE: Why most classifications are fu

[sowa@xxxxxxxxxxx]

Chris,

I view talk about possible worlds as a kind of Gedanken experiment.  Such discussions can be very helpful in discussing the issues in an informal way.  They are useful heuristics, and I encourage people to use whatever heuristics they find helpful.

But the end result in physics is based on the formalism and its predictions about observable quantities.  I believe that the same criteria are appropriate for any other field:  use whatever heuristics are helpful, but the only concrete results are in the formal or formalizable statements.

JFS
>> Could you please give one example of a problem that can be solved by
>> Lewis's approach, but not by Dunn's laws and facts.

CM
> You set the bar too high; I can't give an example that CANNOT be solved by
> Dunn's approach. All I can say is that Lewis provided world-based
> solutions to, e.g., the analysis of modality, the analysis of intensional
> entities, and the problem of mental content, among others, and that, to my
> knowledge, no solutions to those problems exist in terms of laws and
> facts.

I haven't studied all of Lewis's writings, but what I have read sound very much like Gedanken experiments.  They're interesting heuristics. But I wouldn't call them solutions unless they were stated in logic or in some very clear NL that could be translated to logic.

> (For another thing, I don't think there has been any detailed
> philosophical account of what laws and facts even ARE in anything other
> than a purely formal sense. It is thus not even clear how one would
> develop Dunn's account to metaphysical ends.)

The general method for mapping a Kripke model to a Dunn model is to treat any statement that is true about a world w as a fact, and any statement that is necessarily true as a law.  That method could be applied to anything that Lewis considers true or necessary in any of his discussions.

But the primary argument for Dunn's method is not merely that it's isomorphic to Kripke's, but that it opens up completely new topics for development.

In particular, Dunn's method allows any insights about laws of any kind to be put in the set of laws.  You can even have different levels of entrenchment among the laws:  laws of logic, laws of nature, the US Constitution, the laws passed by Congress, the laws of New York State, ... down to the laws asserted by your mommy.

Dunn's method opens up very flexible ways of talking about multiple modalities within  the same framework.  For example, the word 'must' is usually considered ambiguous.  But in Dunn's method, it is univocal: it is defined in terms of some law, which could be at any level from a law by your mommy up to a law of nature or logic.

As far as metaphysics goes, I believe that Dunn's method is far more fruitful and clearer than anything I've read in Lewis's writings. I tried to discuss some of those issues in my worlds.pdf and laws.htm articles.

John

_________________________________________________________________
Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J    (01)