I really like the new tagging system. I think it helps organize the forum and I'm really happy the admins have added it. That said, I have some suggestions for how we can make it even better.
 

Deleting the null tags

Right now there are 46 tags that don't have any posts on them. Almost a quarter of the tags are empty. These tags clutter up the tag page without adding anything of value to the forum. I think there should be a rule that you can only create a new tag if you can actually add it to at least one existing post. That way we can prevent unnecessary clutter.
 

No more tags for individuals

There are a bunch of tags for individuals. But why should we have a Peter Singer tag when we can just link to the page of Peter Singer? I find it rather awkward to discuss individuals instead of discussing their ideas. I suspect this might lead to hero-worship or unnecessary psychoanalysis. Maybe this is an unpopular opinion but I don't think we should have any tags for individuals on this forum.
 

Deleting double tags

We have a bunch of tags that describe the same concept another tag already describes. Population Ethics is the same as Population ethics and Patient Altruism is interchangeable with Patient longtermism. These are some obvious examples, but there are some tags that are more debatable, which brings me to:
 

A system for "subtags"

Some concepts are a subcategories of broader concepts. For example: Population Ethics is a branch of Normative Ethics. Maybe we could have a system where some tags are listed under other tags. For example:

• Moral Philosophy
  • Normative ethics
    • Population Ethics
    • Infinite ethics
  • Meta-Ethics
    • Moral Uncertainty
  • Applied ethics
    • Near-Term AI Ethics

This would give a nice overview of the concepts and how they all relate to each other on the tag page. Of course we would still have an alphabetical listing below it in case you want to search for a specific tag that way. This would also make it really easy for the effective altruism wiki to organize their pages.

I also propose that adding a subtag to a post will automatically add said post to the page of its "broader tags". For example: whenever you tag a post with Population Ethics it will also automatically be added to the Normative ethics page and the Moral Philosophy page. However, the post will only display the tags on the lowest level of the "subtag ladder", so a post with the Population Ethics tag will only display Population Ethics and not Normative ethics and Moral Philosophy. This will also prevent some of the tag clutter I've seen on a few posts.
 

A way for non-mods to delete tags

I saw the Population Ethics/Population ethics situation, but I couldn't fix it myself. I think there should be a way for non-mods to delete or merge tags. You could make it a public vote where at least three users have to agree (or something along those lines). That way you don't give too much power to trolls, but also allow tags to be trimmed without the need to pester the mods. If a subtag system is implemented, a voting system could also be used to categorize those.
 

Write a Tag FAQ

Something like the Wiki-Tag FAQ on LW would be fine. I could write it myself, though someone should probably double-check my writing since I'm not a native English speaker. You could have a link to this FAQ on the tag page, so newcomers can have the tagging system and its purpose explained to them.
 

Have a tag activity page

Have a page where you can see when tags were created and who created them. Maybe you can even track when a tag was added to a post. This should make it easier to catch trolls. A link to this page could be available on the tag page. If a subtag system is implemented this page could also display when a tag becomes a subtag and who voted for it.
 

Create a page for tag edits and discussion

When you go to a tag you can click on "history" to see the history of the tag description and on "discussion" to see comments about said tag. Perhaps we could create a page (or two separate pages) that lays out all this information for every tag simultaneously. This way you can have an overview of the history of all the tag edits and discussions. We could put a link to these pages on the tag page.
 

Completing the tag descriptions

There are a lot of tags that are missing good descriptions. I suggest we make a page that gives users an overview of this issue. Users or the mods could signal if a tag: needs a description, is a stub, needs related pages, needs updating, has very few posts, needs relevance sorting, is a merge candidate, is a split candidate, is a Wiki-Only candidate, is a tag only candidate, is in need of description improvements, has high priority, has other work that needs to be done, or should be deleted. Something like the Wiki-dashboard. Maybe people who write a lot of tag descriptions could even be rewarded with some karma to help incentivize completion.
 

Create a discussion thread

Create a discussion thread where people can leave their suggestions/critiques of the tagging system. Put a link to this discusion thread and to "Propose and vote on potential tags" on the tag page.

Perhaps this post can (temporarily) be the discussion thread? If you have more suggestions or want to discuss one of my suggestions you can leave a comment on this post.