Re: Heap-Set Theory H-S
- From: G. Frege <nomail@invalid>
- Date: Wed, 30 Jan 2008 00:34:12 +0100
On Tue, 29 Jan 2008 15:03:58 -0800 (PST), Zaljohar@xxxxxxxxx wrote:
I see. While on the other hand, ' seems to "light" to me. :-)
but Frege I also had [ ] in my mind , but I see it too heavy for that
purpose.
I wanted the lightest symbol,
Moreover, one might mistake them for quotation marks. ;-)
I don't think so. :-)
Ideally we would use spaces to do the job
Uhhh... :-)
so for example we say z = xy
Well ... But this way you would not even be able to _formulate_:
so xy here is actually the heap of xy
[[x, y], z] = [x, y, z].
Indeed! (Yo may count on me here! :-)
but I feel that a lot of objections will be raised against that
Well... Another point, I guess: [ ] resembles the usually braces { }
so I preferred to use the lightest symbol like ' ' , so 'xy'
would be the nearest to xy, I guess?
used for sets.
Yes. Parthood has indeed some "features" in common with the usual set
I like your notation c to represent 'is a constituent of' or what I
call ' is part of' .
theoretic "c", I guess.
Especially
[a, b] c [a, b]
etc., of course.
Good idea. After all they ARE, from the viewpoint of heaps. (Since a set
But what is interesting to me is that if we stipulate that all sets
are atomic (NOTE: this is not the standard, that standard is to
stipulate that all singleton sets are atomic: Review David Lewis in
Parts of Classes) However in this theory I stipulated that all sets
are atomic,
is not a "molecular" heap - but just a heap consisting of that very set.
It's an atom.)
Very nice approach. Yes, it's certainly a nice idea to combine set
and from comprehension in this theory we can actually get the heap of
any sets that we fulfill P(x) for any P(x) provided that there should
exist at least one set for which P holds.
theory with "heap theory". Or with other words, to do set theory in the
context of a heap framework. (This way we might get the best from both
theories, I guess.)
And right, imho it's natural (though not necessary from a logical point
of view - it seems) to rule out the "empty heap".
My personal argument (again a quote):
"... of course there's no "empty heap", if there are no objects
there is simply no heap, it "vanishes".
Yes. It's a nice approach, indeed.
So in this way we can have the heap of all ordinals, the heap of all
sets, the heap of all well founded sets, the heap of all sets
bijective to a set, the heap of all sets bigger than a set, etc...,
the heap of all sets other than a set, the heap of all sets that are
not members of a set etc....
F.
--
E-mail: info<at>simple-line<dot>de
.
- Follow-Ups:
- Re: Heap-Set Theory H-S
- From: Zaljohar
- Re: Heap-Set Theory H-S
- References:
- Heap-Set Theory H-S
- From: Zaljohar
- Re: Heap-Set Theory H-S
- From: Zaljohar
- Re: Heap-Set Theory H-S
- From: G . Frege
- Re: Heap-Set Theory H-S
- From: Zaljohar
- Heap-Set Theory H-S
- Prev by Date: Re: Gödel's system P, Principia Mathematica, and the reducibility axiom
- Next by Date: Re: What's the weakest metatheory in which Goedel's theorem can be proved?
- Previous by thread: Re: Heap-Set Theory H-S
- Next by thread: Re: Heap-Set Theory H-S
- Index(es):
Relevant Pages
|
Loading