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WikiProject Mathematics (Rated C-class, High-importance)
WikiProject Mathematics
This article is within the scope of WikiProject Mathematics, a collaborative effort to improve the coverage of Mathematics on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
Mathematics rating:
C Class
High Importance
 Field:  Foundations, logic, and set theory
One of the 500 most frequently viewed mathematics articles.

Symbols ⊊ and ⊋[edit]

The section "⊂ and ⊃ symbols" only mentions the symbols ⊊ and ⊋ as something some authors prefer not to use. The reference there does not mention these symbols. It would be useful to find a positive reference for authors that do prefer to use ⊊ and ⊋ for proper sub/supersets, and use ⊂ and ⊃ where the two sets may be equal. — Preceding unsigned comment added by Kopretinka (talkcontribs) 10:14, 27 November 2017 (UTC)

There's a whole list at Wikipedia talk:WikiProject Mathematics/Conventions#Literature survey. That's part of what I would call an obsolete discussion from more than a decade ago, but should be a good resource to find authors who do various things. --Trovatore (talk) 19:27, 27 November 2017 (UTC)

Proper subset/superset[edit]

It would be useful if the article explains or defines what the proper subset and superset *is* before introducing the symbols for them. (talk) 16:32, 12 January 2018 (UTC)

This is done in the section on definitions, which comes before the section on this notation. --Bill Cherowitzo (talk) 20:03, 12 January 2018 (UTC)
No it's not. I agreed with the OP, it is not clear at all from this article what a *proper* sub-/superset is from this article. I had to look this up on another website. JHBonarius (talk) 08:13, 11 March 2018 (UTC)
Please indicate what part of this is not clear.

If A is a subset of B, but A is not equal to B (i.e. there exists at least one element of B which is not an element of A), then

  • A is also a proper (or strict) subset of B; this is written as
or equivalently
  • B is a proper superset of A; this is written as
I copied that from the definitions section. What would you suggest to improve the wording? --Bill Cherowitzo (talk) 18:16, 11 March 2018 (UTC)