List of mathematical theories: It present at the same level some wide areas of mathematics ( set theory ) and some very specialized method ( Iwasawa theory ).  So, it does not contain any relevant encyclopedic content.  D.Lazard ( talk ) 08:50, 30 April 2024 (UTC) [ reply ] Note:  This discussion has been included in the list of Mathematics-related deletion discussions .  D.Lazard ( talk ) 08:50, 30 April 2024 (UTC) [ reply ] Comment .  The nominator is saying that WP:LSC is not satisfied in a meaningful way.  Having "theory" included in the title was probably good enough in 2004, when the list page was first created.   The list is hardly complete: sieve theory isn't there, for example.  While mathematicians recognise as "theory" any coherent area with enough definitions, results and characteristic ideas, this kind of theory is nothing like a scientific theory .  So the list may be of little or no help to non-mathematicians.  I would suggest first a division by subject headings, such as "theories in topology".  I mean, this is potentially a useful list, just as a list of problems or a list of theorems would be, but there should be more explanation and apparatus.  Charles Matthews ( talk ) 09:14, 30 April 2024 (UTC) [ reply ] Note:  This discussion has been included in the list of Lists-related deletion discussions .  WC Quidditch ☎ ✎ 10:45, 30 April 2024 (UTC) [ reply ] Comment .  For having this article, we must have a sourced definition of the concept of a mathematical theory; the unsourced three lines of Mathematical theory are far to be sufficients.  Moreover, in mathematics, some other words are used with a similar meaning, such as "geometry", "algebra", "calculus", and "analysis".  For example, projective geometry means "projective-space theory"; commutative algebra stands for "commutative-ring theory", to be compared with ring theory , which deals with non-necessarily commutative rings; integral calculus stand for "theory of integrals"; real analysis stands for "theory of real functions".  So, without a reliably sourced definition of the concept of a mathematical theory, this article is pure original synthesis .  D.Lazard ( talk ) 11:00, 30 April 2024 (UTC) [ reply ] Yes, that's a reasonable argument, but I would like to see it on Talk:List of mathematical theories because there is plenty to say.  To use your examples, axiomatic set theory is a number of choices of axiomatic theory , while Iwasawa theory was originally "Iwasawa's analogue of the Jacobian", which John Coates renamed, and over the course of half a century became a major subfield of algebraic number theory , which is not an axiomatic theory so much as the study of algebraic number fields .  To be really helpful, this sort of information, including the genesis of a theory, should be tabulated.  Charles Matthews ( talk ) 11:29, 30 April 2024 (UTC) [ reply ] Keep , but rename to list of mathematical theories and subfields .  Such a list could have sections for eponymous theories such as Morse theory and Iwasawa theory , and for other special cases.  The distinction between commutative algebra and the subfield of ring theory dealing with commutative rings is that commutative algebra is also concerned with modules over such rings.  That is seen in the way the earlier name ideal theory was revised, modules over a ring being a generalisation of ideals in a ring, an innovation in the school of Emmy Noether .  The list has been harmless enough for 20 years.  No need to delete, when we can adjust the scope a bit.  Charles Matthews ( talk ) 08:45, 1 May 2024 (UTC) [ reply ] Comment : I looked at that list, but it seems more like a category than an article.  For example, wikipedia has a Category:Duality theories .  -- SilverMatsu ( talk ) 16:36, 3 May 2024 (UTC) [ reply ] Relisted to generate a more thorough discussion and clearer consensus.  Please add new comments below this notice.  Thanks, North America 1000 08:26, 8 May 2024 (UTC) [ reply ] Delete , I agree with the nominator.  But it would be ok as a category.  Gumshoe2 ( talk ) 16:21, 10 May 2024 (UTC) [ reply ] Rename per Charles Matthews.  Informative article.  Raymond3023 ( talk ) 13:58, 13 May 2024 (UTC) [ reply ] Relisted to generate a more thorough discussion and clearer consensus.  Please add new comments below this notice.  Thanks, Doczilla Ohhhhhh, no!  07:16, 16 May 2024 (UTC) [ reply ] Keep and rename, per those above.  This would also benefit from some prefatory text describing what qualifies a topic as suitable for inclusion in the list.  BD2412 T 13:06, 16 May 2024 (UTC) [ reply ] Keep this page as a valuable resource - maybe it would be better renamed or changed to a category or whatever, but the lack of organization in the higher math fields can be extremely confusing (especially for people who are math hobbyists rather than university mathematicians).  We need more resources like this, not fewer.  So maybe it is WP:INDISCRIMINATE , but it is a good resource, so keep per WP:IAR .  Love, Cassie.  ( Talk to me! ) 15:04, 22 May 2024 (UTC) [ reply ] The above discussion is preserved as an archive of the debate.  Please do not modify it.  Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review ).  No further edits should be made to this page.

Discussion outcome: keep