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1. • CommentRowNumber1.
   • CommentAuthorDavid_Corfield
   • CommentTimeJun 20th 2016
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItexDo others also not see the category theoretic diagrams of [[dependent sum natural deduction - table]]?

   Do others also not see the category theoretic diagrams of dependent sum natural deduction - table?

2. • CommentRowNumber2.
   • CommentAuthorMatt Earnshaw
   • CommentTimeJun 20th 2016
   • PermaLink
   Author: Matt Earnshaw
   Format: MarkdownItexFor some reason they were (broken) hotlinks to quicklatex.com rather than inline mathjax. Looking at [revision #3](https://ncatlab.org/nlab/revision/dependent+sum+natural+deduction+-+table/3), I suppose the issue was that $ p_1 $ overlaps $ \in $ in the type formation diagram (at least it does on my system), so I have (speculatively) rolled it back to that with an extra space thrown in.

   For some reason they were (broken) hotlinks to quicklatex.com rather than inline mathjax. Looking at revision #3, I suppose the issue was that $p_1$ overlaps $\in$ in the type formation diagram (at least it does on my system), so I have (speculatively) rolled it back to that with an extra space thrown in.

3. • CommentRowNumber3.
   • CommentAuthorDavid_Corfield
   • CommentTimeJun 20th 2016
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItex[[dependent product natural deduction - table]] also has a problem, but now there are only two versions and neither shows anything.

   dependent product natural deduction - table also has a problem, but now there are only two versions and neither shows anything.

4. • CommentRowNumber4.
   • CommentAuthorTobyBartels
   • CommentTimeJul 8th 2016
   • (edited Jul 8th 2016)
   • PermaLink
   Author: TobyBartels
   Format: MarkdownItexI started to fill in the missing diagrams in [[dependent product natural deduction - table]]. Unfortunately, these diagrams don\'t really make sense to me ―I think that they\'re using a bad paradigm―, and I can\'t figure out what all of them should be. Presumably Urs knows.

   I started to fill in the missing diagrams in dependent product natural deduction - table. Unfortunately, these diagrams don't really make sense to me ―I think that they're using a bad paradigm―, and I can't figure out what all of them should be. Presumably Urs knows.

5. • CommentRowNumber5.
   • CommentAuthorUrs
   • CommentTimeJul 9th 2016
   • PermaLink
   Author: Urs
   Format: MarkdownItexThey were supposed to depict the interpretation of the type theory in a categry, with dependent types as display morphisms, etc. I might try to look into it again later.

   They were supposed to depict the interpretation of the type theory in a categry, with dependent types as display morphisms, etc. I might try to look into it again later.

6. • CommentRowNumber6.
   • CommentAuthorDavid_Corfield
   • CommentTimeJan 28th 2018
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItexComing back to these tables, [[dependent sum natural deduction - table]]: should we have $(x, a)$ as the label on the horizontal arrow in the row for term introduction, then $t$ similarly for the next row? And the diagram in the type formation row is OK? How about if we had $p_1: X \to A \in \mathcal{C}/X$? And can't we fit the $p_2$ relations as we do at [[product natural deduction - table]]? [[dependent product natural deduction - table]]: lacks diagrams for some rows.

   Coming back to these tables,

   dependent sum natural deduction - table: should we have $(x, a)$ as the label on the horizontal arrow in the row for term introduction, then $t$ similarly for the next row? And the diagram in the type formation row is OK? How about if we had $p_1: X \to A \in \mathcal{C}/X$? And can’t we fit the $p_2$ relations as we do at product natural deduction - table?

   dependent product natural deduction - table: lacks diagrams for some rows.

7. • CommentRowNumber7.
   • CommentAuthorDavid_Corfield
   • CommentTimeJan 28th 2018
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItexI dabbled with a revised version at [[dependent sum natural deduction - table]], leaving the original for comparison. Not sure about the term introduction row.

   I dabbled with a revised version at dependent sum natural deduction - table, leaving the original for comparison. Not sure about the term introduction row.

8. • CommentRowNumber8.
   • CommentAuthorUrs
   • CommentTimeJan 28th 2018
   • PermaLink
   Author: Urs
   Format: MarkdownItex> should we have $(x, a)$ as the label on the horizontal arrow in the row for term introduction, then $t$ similarly for the next row? Yes, that seems good. The diagrams represent the syntax on the left only somewhat coarsely. Not sure if it can be made more precise while still being brief enough for an overview table instead of a detailed account.

   should we have $(x, a)$ as the label on the horizontal arrow in the row for term introduction, then $t$ similarly for the next row?

   Yes, that seems good.

   The diagrams represent the syntax on the left only somewhat coarsely. Not sure if it can be made more precise while still being brief enough for an overview table instead of a detailed account.

9. • CommentRowNumber9.
   • CommentAuthorMike Shulman
   • CommentTimeJan 29th 2018
   • PermaLink
   Author: Mike Shulman
   Format: MarkdownItexYes, e.g. there's not much non-tautological that can be said briefly about the semantic computation rule for $p_2$.

   Yes, e.g. there’s not much non-tautological that can be said briefly about the semantic computation rule for $p_2$.