Discussion of Homotopy Type Theory and Univalent Foundations
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From: Martin Escardo <escardo...@googlemail.com>
To: Alexander Kurz <axh...@gmail.com>, Michael Shulman <shu...@sandiego.edu>
Cc: Thorsten Altenkirch <Thorsten....@nottingham.ac.uk>,
	Thomas Streicher <stre...@mathematik.tu-darmstadt.de>,
	"homotopyt...@googlegroups.com" <homotopyt...@googlegroups.com>
Subject: Re: [HoTT] Re: Where is the problem with initiality?
Date: Fri, 1 Jun 2018 10:55:43 +0100	[thread overview]
Message-ID: <a1f83d0e-c744-443d-5051-7b31b6864679@googlemail.com> (raw)
In-Reply-To: <37CBB960-C4F1-4B97-92E6-28462A0591C1@gmail.com>

On 31/05/18 20:02, Alexander Kurz wrote:

> I am interested in this question of translating the untyped stuff we write on the page into type theory.
> 
> To give a concrete example of what I am thinking of as untyped, but nevertheless conceptual and structural mathematics, I would point at Tom Leinster’s elegant description of the solution to the problem of Buffon’s needle, see the first paragraphs of the section “What is category theory?” at https://golem.ph.utexas.edu/category/2010/03/a_perspective_on_higher_catego.html
> 
> I call this argument type free because I see no obvious or canonical way to make the types precise enough in order to implement the proof in, say, Agda. Even if this can be done, it is still important that mathematicians can discuss this argument first without having to make the types precise. So there will always be mathematics outside of type theory.

I don't understand why you call this argument untyped. Do you feel that 
a formalization in set theory, which is untyped, would be easier than a 
formalization in type theory? How is untypedness helping with this argument?

Martin


  reply	other threads:[~2018-06-05  7:30 UTC|newest]

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-22  5:46 Michael Shulman
2018-05-22 16:47 ` Ambrus Kaposi
2018-05-23 16:26 ` [HoTT] " Thorsten Altenkirch
2018-05-24  5:52   ` Michael Shulman
2018-05-24  8:11     ` Thorsten Altenkirch
2018-05-24  9:53       ` Ambrus Kaposi
2018-05-24 17:26         ` Michael Shulman
2018-05-26  9:21           ` Thomas Streicher
2018-05-26 11:47             ` Michael Shulman
2018-05-26 16:47               ` stre...
2018-05-27  5:14                 ` Bas Spitters
2018-05-28 22:39 ` Michael Shulman
2018-05-29  9:15   ` [HoTT] " Thorsten Altenkirch
2018-05-29 15:15     ` Michael Shulman
2018-05-30  9:33       ` Thomas Streicher
2018-05-30  9:37         ` Thorsten Altenkirch
2018-05-30 10:10           ` Thomas Streicher
2018-05-30 12:08             ` Thorsten Altenkirch
2018-05-30 13:40               ` Thomas Streicher
2018-05-30 14:38                 ` Thorsten Altenkirch
2018-05-30 10:53           ` Alexander Kurz
2018-05-30 12:05             ` Thorsten Altenkirch
2018-05-30 19:07               ` Michael Shulman
2018-05-31 10:06                 ` Thorsten Altenkirch
2018-05-31 11:05                   ` Michael Shulman
2018-05-31 19:02                     ` Alexander Kurz
2018-06-01  9:55                       ` Martin Escardo [this message]
2018-06-01 17:07                       ` Martín Hötzel Escardó
2018-06-01 17:43                         ` Eric Finster
2018-06-01 19:55                           ` Martín Hötzel Escardó
2018-06-01 20:59                             ` András Kovács
2018-06-01 21:06                               ` Martín Hötzel Escardó
2018-06-01 21:23                                 ` Michael Shulman
2018-06-01 21:53                                   ` Eric Finster
2018-06-01 22:09                                     ` Michael Shulman
2018-06-02 15:06                                       ` Eric Finster
2018-06-05 20:04                                         ` Michael Shulman
2018-06-02  5:13                                 ` Thomas Streicher
2018-06-01 21:52                               ` Jasper Hugunin
2018-06-01 22:00                                 ` Eric Finster
2018-06-01 21:27                           ` Matt Oliveri
2018-06-02  5:21                             ` Ambrus Kaposi
2018-06-02  6:01                               ` Thomas Streicher
2018-06-02 14:35                           ` Thorsten Altenkirch
2018-05-30 13:30             ` Jon Sterling
2018-06-05  7:52             ` Andrej Bauer
2018-06-05  8:37               ` David Roberts
2018-06-05  9:46                 ` Gabriel Scherer
2018-06-05 22:19                 ` Martín Hötzel Escardó
2018-06-05 22:54                   ` Martín Hötzel Escardó
2018-06-05 22:12               ` Richard Williamson
2018-06-06 15:05                 ` Thorsten Altenkirch
2018-06-06 19:25                   ` Richard Williamson
2018-05-29 14:00   ` Jon Sterling
2018-05-30 22:35     ` Michael Shulman
2018-05-31 10:48       ` Martín Hötzel Escardó
2018-05-31 11:09         ` Michael Shulman

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