Re: Roles, again

phayes@cs.uiuc.edu (Pat Hayes)
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Date: Fri, 8 Sep 1995 15:14:41 -0600
To: "Nicola Guarino" <guarino@ladseb.pd.cnr.it>,
        "Pat Hayes" <phayes@cs.uiuc.edu>, cg@cs.umn.edu, srkb@cs.umbc.edu
From: phayes@cs.uiuc.edu (Pat Hayes)
Subject: Re: Roles, again
Cc: "Pierdaniele Giaretta" <giaretta@ipdunidx.unipd.it>,
        "Massimiliano Carrara" <carrara@cs.umbc.edu>
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At  1:28 PM 9/8/95 +0100, Nicola Guarino wrote:
>On 8 Sep 95 Pat Hayes wrote:
>
>>>
>>>>On 28-AUG-1995 John Sowa wrote:
......  Form is
>>>>defined as the top (or Entity) with the differentia Firstness; Role is
>>>>Entity with differentia Secondness; and Mediation is Entity with
>>>>differentia Thirdness.
>>
>>Oh, thats a GREAT help. There were three incomprehensible words and now
>>there are four. Could I put in a plea for good old Fregean extensionality
>>here? In spite of its evident ability to intellectually seduce, I cant see
>>a single practical reason why we should take any of this Peircian mysticism
>>seriously: it belongs with Freemasonry.
>>
>
>I don't know whether it's Freemasonry, what is certainly true is that these
>words are incomprehensible but at the same time stimulating. 

Not to me. They seem simply confused. Every attempt to make them precise
has failed.

>What is needed
>is an effort for translating the relevant ideas (if any) into ordinary
>logic, I agree with Pat on this point. 

Not quite. My suggestion is simpler: that these words be simply ignored and
ordinary logic be used to do the job at hand. 

Unfortunately, the sort of
>"mysticism" which ssems to permeate John's words doesn't help too much.
>
>However, I'm convinced that there *are* relevant ideas hidden behind this
>mysticism. The notion which lies behind, as far as I have understood, is
>that of *dependence* (to be more precise, "conceptual" or "notional"
>dependence, as Peter Simons calls it in his book on parts [p. 297]). A
>predicate like Mother, for instance, is dependent on Child if there cannot
>be a mother without a child ("Secondness").

(x)((Mother x) implies (exist y)(Child y) & (x is-mother-of y)))

I know that this means that Foot depends on Toe, just as Person depends on
date-of-birth. If you really, really want nonextensionality, then use a
modality:

(x)((Mother x) implies Neccessary((exist y)(Child y) & (x is-mother-of y))))

Modalities are like drugs: if you really want them, you should be able to
have them, but the real cure is to keep off them altogether.

> A predicate like Person, on the
>other hand, can be conceived as indepedent if the fact that X is a Person
>does not necessarily imply that somebody else is an instance of another
>predicate ("Firstness").

Ah, careful. It does, I suggest, imply that some THING must be an instance
of another prediacte and have a relation to X. For example a Person must
have their time of birth. Every concept we have gets its meaning from the
network of relations that bind it to other concepts. There arent any
'primitive' ones. Exercise: consider, if you can, an orange which is shiny,
purple, oval, used to make savory dinners, and tastes like an eggplant. Its
just a mistake to call it an 'orange', right? But if Orange is
'independent' and had Firstness, we can just assert that this thing is an
orange (a very unusual orange) in spite of any other properties or
relations it might have to anything else. This is just Aristotelian
essentialism rearing its seductive old head again.

 Finally, if we have reified situations (or states
>of affairs, eventualities, or whatever) in our domain, we can think that the
>fact that X is a Mother implies the existence of a "Motherhood" situation
>("Thirdness").

Why isnt motherhood(ness) simply the relation of being-a mother-of? Why
should we reify such murky entities as these 'situations'? (Incidentally,
these arent Barwisean 'situations': in that situation theory, a situation
has a spatiotemporal location. What is the motherhood 'state of affairs'?
All the moments of birth? 

>This notion of dependence is very akin to that of "Foundation", extensively
>(but informally) discussed by Husserl in his "Logical Investigations". 

Thanks for opening the door wide enough to let me see Husserl inside. I'll
leave this discussion now.

Pat

PS sorry about the quantifier slip, you are right.

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