From: "Robert J. MacG. Dawson" <Robert.Dawson@STMARYS.CA>
To: categories@mta.ca
Subject: Re: Categories ridiculously abstract
Date: Sat, 02 Dec 2000 09:34:22 -0400 [thread overview]
Message-ID: <3A28FA5E.9640F981@stmarys.ca> (raw)
In-Reply-To: <E141XXT-00048c-00@plover.dpmms.cam.ac.uk>
Tom Leinster wrote:
>
> Michael Barr wrote:
> >
> > And here is a question: are categories more abstract or less abstract than
> > sets?
>
> A higher-dimensional category theorist's answer:
> "Neither - a set is merely a 0-category, and a category a 1-category."
>
> There's a more serious thought behind this. Sometimes I've wondered, in a
> vague way, whether the much-discussed hierarchy
>
> 0-categories (sets) form a (1-)category,
> (1-)categories form a 2-category,
> ...
>
> has a role to play in foundations. After all, set-theorists seek to found
> mathematics on the theory of 0-categories; category-theorists sometimes talk
> about founding mathematics on the theory of 1-categories and providing a
> (Lawverian) axiomatization of the 1-category of 0-categories; you might ask
> "what next"? Axiomatize the 2-category of (1-)categories? Or the
> (n+1)-category of n-categories?
Surely we should start with the set of (-1)-categories? <gd&r>
-Robert Dawson
next prev parent reply other threads:[~2000-12-02 13:34 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2000-11-30 17:30 Tom Leinster
2000-12-01 22:19 ` Michael MAKKAI
2000-12-06 19:18 ` DR Mawanda
2000-12-02 13:34 ` Robert J. MacG. Dawson [this message]
-- strict thread matches above, loose matches on Subject: below --
2000-12-04 5:30 Vaughan Pratt
2000-11-29 13:39 John Duskin
2000-11-29 16:48 ` Michael Barr
2000-11-30 20:52 ` Todd Wilson
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