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1. • CommentRowNumber101.
   • CommentAuthoratmacen
   • CommentTimeNov 7th 2018
   • PermaLink
   Author: atmacen
   Format: MarkdownItexRe #99: Thanks. Re #100: I'm not arguing for (i) over (ii), but I don't see how (ii) in $[C^op,Set]$ is a way of talking about (i) in $C$. I don't know what (i) in $C$ even means, since $C$ may not have a universe. There seems to be a serious misunderstanding about what (i) and (ii) are.

   Re #99: Thanks.

   Re #100:

   I’m not arguing for (i) over (ii), but I don’t see how (ii) in $[C^op,Set]$ is a way of talking about (i) in $C$. I don’t know what (i) in $C$ even means, since $C$ may not have a universe. There seems to be a serious misunderstanding about what (i) and (ii) are.

2. • CommentRowNumber102.
   • CommentAuthorMike Shulman
   • CommentTimeNov 7th 2018
   • PermaLink
   Author: Mike Shulman
   Format: MarkdownItexThe partiality of (i) in $C$ is also external, so it doesn't need a universe.

   The partiality of (i) in $C$ is also external, so it doesn’t need a universe.

3. • CommentRowNumber103.
   • CommentAuthoratmacen
   • CommentTimeNov 7th 2018
   • PermaLink
   Author: atmacen
   Format: MarkdownItexI reread some earlier comments on this subthread about (i) vs (ii). I think you're right, and I misunderstood what Dan wants. It now seems to me like he might count natural families $\Pi X\,:\,Ob(C),\,(Hom(y X,Tm))_\bot$ as (i). And as far as I understand, this is essentially what you get from an element of $Tm_\bot$ constructed in the semantic logical framework without funny tricks.

   I reread some earlier comments on this subthread about (i) vs (ii). I think you’re right, and I misunderstood what Dan wants. It now seems to me like he might count natural families $\Pi X\,:\,Ob(C),\,(Hom(y X,Tm))_\bot$ as (i). And as far as I understand, this is essentially what you get from an element of $Tm_\bot$ constructed in the semantic logical framework without funny tricks.