Discussion of Homotopy Type Theory and Univalent Foundations
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From: Thomas Streicher <stre...@mathematik.tu-darmstadt.de>
To: Michael Shulman <shu...@sandiego.edu>
Cc: "HomotopyT...@googlegroups.com" <homotopyt...@googlegroups.com>
Subject: Re: [HoTT] Categories with 2-families
Date: Wed, 7 Mar 2018 18:09:02 +0100	[thread overview]
Message-ID: <20180307170902.GA5070@mathematik.tu-darmstadt.de> (raw)
In-Reply-To: <CAOvivQwEH927TWF2OMFpeg9YYSArDDGiQRmtfJGjj0qsJzSQDA@mail.gmail.com>

On Mon, Mar 05, 2018 at 01:29:56PM -0800, Michael Shulman wrote:
> By a standard construction (described for example at
> https://ncatlab.org/nlab/show/categorical+model+of+dependent+types),
> categories with families are equivalent to categories with attributes,
> i.e. to comprehension categories that are discrete fibrations.

That's misleading I think. One rather should think categories with
attributes as full comprehension categories (like any surjective map
from a class S to Ob(C) allows one construct a category equivalent to
C whose collection of objects is S).

Thomas

  reply	other threads:[~2018-03-07 17:09 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-05 21:29 Michael Shulman
2018-03-07 17:09 ` Thomas Streicher [this message]
2018-03-07 20:15   ` [HoTT] " Peter LeFanu Lumsdaine
2018-03-07 20:30     ` Thomas Streicher
2018-03-07 20:39       ` Peter LeFanu Lumsdaine
2018-03-07 21:01         ` Thomas Streicher
2018-03-07 22:16           ` Peter LeFanu Lumsdaine
2018-03-08 10:11             ` Thomas Streicher
2018-03-07 21:20       ` Michael Shulman

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