Talk:Outline of category theory

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I'd add triangulated category, but I don't know which section it should be in. Michael Hardy 02:50, 2 Apr 2005 (UTC)

It's now under Additive structure, which is reasonable - categories of modules, sheaves of abelian groups, that's the right general context.

Charles Matthews 12:01, 2 Apr 2005 (UTC)

A small cartesian closed concrete category

Is there a cartesian closed concrete category which is small enough to write out explicitly? It would be helpful in learning about map objects, exponentiation, distributivity and other topics. Can such a category be made with binary numbers for instance? Is there a way to avoid having an infinite number of objects?

Thanks, ... PeterEasthope (talk) 15:19, 13 February 2008 (UTC)[reply]

Sure. Every Heyting algebra is a cartesian closed category, with meet for product and implication for the closed structure. Lots of finite examples, e.g. any finite chain, any finite power set, any finite product of finite chains, a kite with a tail, etc. --Vaughan Pratt (talk) 22:46, 13 July 2011 (UTC)[reply]

Quick explanation of Wikipedia outlines

"Outline" is short for "hierarchical outline". There are two types of outlines: sentence outlines (like those you made in school to plan a paper), and topic outlines (like the topical synopses that professors hand out at the beginning of a college course). Outlines on Wikipedia are primarily topic outlines that serve 2 main purposes: they provide taxonomical classification of subjects showing what topics belong to a subject and how they are related to each other (via their placement in the tree structure), and as subject-based tables of contents linked to topics in the encyclopedia. The hierarchy is maintained through the use of heading levels and indented bullets. See Wikipedia:Outlines for a more in-depth explanation. The Transhumanist 00:04, 9 August 2015 (UTC)[reply]