What's the tag (formal-systems) for?

What's the tag for?

Just meta theory? Meta theory and formal proofs? Other options?

Edit: In view of the comments to this question and due to the fact there have been a lot of questions asking for formal proofs, should the tag (formal-proofs) be created? Most of these questions are either about natural deduction or Hilbert type system, There is a tag called (natural-deduction), but there's nothing for the rest. I think getting rid of (natural-deduction) and creating (formal-proofs) is appropriate. The other option is to include the tag (Hilbert-system) or similar.

• Diplomacy, politics and other formal channels between conglomerates of humans. – Asaf Karagila Jun 11 '14 at 9:41
• A quick perusal of the questions seems to suggest we don't need the tag. It's been applied to questions on propositional-calculus, first-order-logic, formal-languages, lambda-calculus, computability, computational-complexity, which are all more descriptive than formal-systems. Apart from a hypothetical question on Hofstadter's MU puzzle, I'm having trouble thinking of a formal-systems question that would not fit into one of the above listed tags. – user642796 Jun 11 '14 at 12:16
• @ArthurFischer So what happens now? Should it be banned? By the same token isn't the tag (analysis) in the same boat as (formal-systems)? – Git Gud Jun 11 '14 at 13:23
• @GitGud: Thankfully the formal-systems tag is small enough that we could remove it from all questions within a fairly short period of time, a short time after which it would be deleted from the system. The analysis tag is somewhat too big for that, so if there is consensus that it carries too little information, it might be a candidate for burnination/blacklisting. (I almost feel the same way about the logic tag.) – user642796 Jun 11 '14 at 13:57
• @ArthurFischer I will help out in removing the (formal-systems) tag. I think the (logic) tag is appropriate because MSE doesn't deal only with mathematical logic and the (logic) tag might encompass some of the non-mathematical logic questions. Regarding (analysis), should I open a new question or will you? – Git Gud Jun 11 '14 at 14:02
• @ArthurFischer I am not sure how this discussion diverged to (analysis) tag, but there are people who would prefer keeping the tag. It was discussed in chat; I don't remember discussion about this tag on meta. – Martin Sleziak Jun 12 '14 at 7:59
• @MartinSleziak It's clear how (analysis) came up in the conversation, its in the same position as (formal-systems). From what I can see in the chat, the reasons for not removing the tag are logistics. That doesn't seem good enough to me, specially since SE can deal with them easily. – Git Gud Jun 12 '14 at 10:05
• Although t.b. is not active at MSE at the moment, I do respect his opinion. So his opposition against removing (analysis) is sufficient to me to say that this should not be done without previous discussion and reaching some kind of community consensus. (And in general, I think that removing big tags, like homework or analysis, should not be done without discussion on meta. – Martin Sleziak Jun 12 '14 at 10:12
• @MartinSleziak I agree. In fact I suggested creating a new question for that effect in a comment above. – Git Gud Jun 12 '14 at 10:13