Talk:Element (category theory)

Requested move

 * The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section. 

The result of the move request was: No move. Cúchullain t/ c 15:26, 25 March 2013 (UTC)

Element (category theory) → Functor of points – Relisted. Will leave a note at WT:MATH. Favonian (talk) 21:09, 16 March 2013 (UTC) More standard. Taku (talk) 23:52, 9 March 2013 (UTC)


 * Question Could some reliable sources be mentioned for the terminology please? Deltahedron (talk) 07:18, 18 March 2013 (UTC)
 * You mean for "functor of points"? As noted below, it's quite a standard term in any book on the scheme theory. For example, Mumford's red book uses this terminology. -- Taku (talk) 23:41, 19 March 2013 (UTC)


 * Oppose "functor of points" is more associated with scheme theory. But one can associate the "elements" of an object in a category with morphisms from a terminal object to that object for all sorts of categories, even those for which there is no geometric or topological interpretation of an element as a point. For example, in the the category of sets, these morphisms correspond to elements of a set; calling these elements "points" would be wrong here. The terminology "element" is used for instance, in Goldblatt's book Topoi: the categorical analysis of logic, section 4.1, toward the end of the section. If the article is about the category theoretic construct, element seems the more general term. --Mark viking (talk) 16:03, 18 March 2013 (UTC)


 * Ok, so maybe "element" may be standard in the topos theory, which I know nothing about. "Functor of points" redirects here, and it is rather an important topic. Perhaps the better solution is create a separate "functor of points" article, which should include the discussion of, for instance, instances in group schemes. -- Taku (talk)
 * The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.