# User talk:HumblePi

## NotZFC template

Good job.

What we might want to do is to put it in its own section, so to get it to look more like the Template:LEM or Template:DNE or Template:AoC or whatever.

I can take that on board and carve it into shape without much trouble. Thank you for crafting the content. --prime mover (talk) 16:26, 23 April 2017 (EDT)

I appreciate the complement. :) I made the image myself in Microsoft Paint, so there shouldn't be any copyright issues. --HumblePi (talk) 17:25, 23 April 2017 (EDT)

## VNH

Please note that pages can be in more than one category.

There is a large number of pages which are being put into the VNH category for no direct reason, in which the pages to which the material refers makes no mention of the VNH that the thing supposedly refers to. I don't understand. Is that because I'm terminally thick or because I'm just stupid?

And another thing I don't udnerstand: why are you removing categories? --prime mover (talk) 20:43, 29 April 2017 (EDT)

The reason why I put most of those pages into the VNH category was because they were theorems about rank, and the definition of rank relies heavily on the Von Neumann Hierarchy, so I thought it would be appropriate. As for the one you put the mistake tag on, I put that in the category because it used the Von Neumann Hierarchy in the lemma, but I can understand why you don't think it should be there, so I'm sorry about that.
The reason why I removed those categories was because the pages that I edited were about classes, but the categories themselves dealt with sets (for example, the Axiom of Foundation Category used the version of the Axiom that was for sets, not classes). I thought it would be a good idea to put those pages in a category that was meant specifically for classes.
I also wanted to get pages out of the ZF-Class Theory category because ZF can't really handle classes.
From now on, I won't change the categories of pages anymore. I'm sorry if I angered you. --HumblePi (talk) 21:59, 29 April 2017 (EDT)
No, don't let someone stop you from editing them. You seem to be very familiar with the subject so I assume you know what you're doing. Some remarks though on categories: we try to keep the number of pages in a category small (say ~ max. 100), so usually it's a bad idea to e.g. add some category as well as one of its subcategories (I'm not saying it was the case here, I have no idea). When you think the creation of a new category is appropriate, it probably is and don't hesitate to make ProofWiki more organized with it. --barto (talk) 02:55, 30 April 2017 (EDT)
You guys obviously know what you're doing so I'll let you ge ton with it. Ignore my concerns, I am generally in a minority of $1$ when it comes to $\mathsf{Pr} \infty \mathsf{fWiki}$ policy. Go ahead. --prime mover (talk) 03:37, 30 April 2017 (EDT)
@prime.mover You're right to be vigilant. That's how everything stays qualitative and without mistakes. I just want to make sure your monitoring does not keep people back from contributing or scare them away. --barto (talk) 03:57, 30 April 2017 (EDT)
Okay no worries, I get too involved.
Considering the class-theoretical stuff has never beena dequately handled, I'll step back and let you guys handle it. We can review the material in due course and see how it can be made coherent and rigorous.
Please steer clear of making too many changes to the existing "set theory" work in order to fit it into the axiomatic structures. We deliberately start from the intuitive definitions of "Set" and "Element" to keep an accessible route in for e.g. an undergraduate level mathematician (yes, axiomatic set theory was not even mentioned when I was an undergrad, everything I have learned I have picked up by teaching myself about it later). We have steadfastly resisted the attempts by certain schools of thought whose approach is to start with the most general and abstract definition of a concept possible, as it then makes the subject too forbidding to a casual user. --prime mover (talk) 04:19, 30 April 2017 (EDT)
I have no desire to change the stuff on set theory (unless it's under one of the "To Do" categories), because that stuff has been handled very well. I'm almost done sorting through the class stuff. Once I'm done with that, I think I'll take a break from classes and then come back to it later.
I put the page with the mistake template and its lemma out of VNH and into the more general class theory. A lot of the pages that I tagged need work, so when I get around to it I would happy to work with you guys. --HumblePi (talk) 10:49, 30 April 2017 (EDT)