Axiom talk:Axiom of Limitation of Size

At the point that this axiom is raised, are we sure that there is actually a "universe" defined? One of the interesting things about ZFC is that there is no such concept as a "universe" and at this stage it can only be an intuitive concept at best, as it can not be inferred from ZFC itself.

In the context of the Godel-Bernays Axioms, it may well be that the universe is defined (I haven't investigated in detail, it's on my bucket list) - and if so it needs to be specifically referenced in that page. We also need to check that it goes to the appropriate page - at the moment "Universe" is a disambiguation page. I suspect we may need either to add a new page to explain what it is in Class Theory or extend the "Universe (Set Theory)" page to suit. --prime mover 06:35, 19 June 2011 (CDT)


 * In reply to the explain tag, and also to the above, old, remark, note that on the main Godel-Bernays page, under "Axioms for Sets" the "universe" is also mentioned. &mdash; Lord_Farin (talk) 13:54, 21 January 2020 (EST)


 * I'm gradually getting to grips with NBG (which may or may not coincide completely with Godel-Bernays or it maybe a subtle variant of it) and my understanding of a "universal class" has expanded. Smullyan and Fitting are very accessible and intelligently presented, and under its influence I'm completely redesigning the way we present this sort of material.


 * Feel free to comment on anything concerning the direction I'm trying to point this thing in; you never know, I may even see if I can get a copy of the Takeushi and Zaring to reconcile the pioneering work done by Asalmon. Now we have access to the complete thread of thought in class theory I can piece together some of the gaps in that presentation that made it more than a bit puzzling. Turns out it's more coherent than I thought. --prime mover (talk) 15:23, 21 January 2020 (EST)