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1. • CommentRowNumber1.
   • CommentAuthorYaron
   • CommentTimeFeb 23rd 2012
   • PermaLink
   Author: Yaron
   Format: MarkdownItexStarted [[presentation of a category by generators and relations]]. This is probably an evil definition (there was an old discussion on this in the context of [[quotient category]]), and there is perhaps a more modern way to do this, so feel free to change the entry. I used "quotient category" as in CWM and mentioned that this is not the definition in the nLab.

   Started presentation of a category by generators and relations. This is probably an evil definition (there was an old discussion on this in the context of quotient category), and there is perhaps a more modern way to do this, so feel free to change the entry. I used “quotient category” as in CWM and mentioned that this is not the definition in the nLab.

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeFeb 23rd 2012
   • (edited Feb 23rd 2012)
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   Author: Urs
   Format: MarkdownItexBy the way, I recently repeatedly came to think that we should have a general entry titled _[[generators and relations]]_ which explains the idea first in full generality (e.g. free construction followed by quotient) and then lists examples. Because I noticed that we have many entries whose definitions invoke "generators and relations" and strictly speaking they should all point to an explanation for what precisely that means.

   By the way, I recently repeatedly came to think that we should have a general entry titled generators and relations which explains the idea first in full generality (e.g. free construction followed by quotient) and then lists examples.

   Because I noticed that we have many entries whose definitions invoke “generators and relations” and strictly speaking they should all point to an explanation for what precisely that means.

3. • CommentRowNumber3.
   • CommentAuthorMike Shulman
   • CommentTimeFeb 23rd 2012
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   Author: Mike Shulman
   Format: MarkdownItex@Yaron: thanks! I added some links from a few places. @Urs: That's an excellent idea! I made a start: [[generators and relations]].

   @Yaron: thanks! I added some links from a few places.

   @Urs: That’s an excellent idea! I made a start: generators and relations.

4. • CommentRowNumber4.
   • CommentAuthorTim_Porter
   • CommentTimeFeb 24th 2012
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   Author: Tim_Porter
   Format: MarkdownItexI have added a brief reference to the links with computads and 2-polygraphs, and also to Mitchell's paper on Rings with several objects which has a neat section on this.

   I have added a brief reference to the links with computads and 2-polygraphs, and also to Mitchell’s paper on Rings with several objects which has a neat section on this.

5. • CommentRowNumber5.
   • CommentAuthorTobyBartels
   • CommentTimeFeb 26th 2012
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   Author: TobyBartels
   Format: MarkdownItexI added a bit to [[generators and relations]], including mention of [[finitely presented objects]] (and a link back from there).

   I added a bit to generators and relations, including mention of finitely presented objects (and a link back from there).