I seemed to have gotten a submit error when I tried to post these a couple of hours ago. Here's my attempt to answer your questions. Thanks to Raemon for also answering.

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Good questions!

• Is there a way to add wiki-links like on the old wiki? I tried using the [[double square brackets]] like on MediaWiki, but this did not work (at least on the new editor).

Not currently. I expect we'll implement a new autocomplete/auto-link on existing pages relatively soon, but this won't automatically create new pages if they don't exist.

• Is there a way to quickly see if a wiki-tag page on a topic already exists? On the creation page, typing something in the box does not show existing pages with that substring. What I'm doing right now is to look on the all tags page (searching with my browser) and also looking at the wiki 1.0 imported pages list and again searching there. I feel like there must be a better way than this, but I couldn't figure it out.

The best way would be with LessWrong's overall search bar (top right of the page). That has a Wiki & Tags section that'll cover all pages. Sorry for not having search clearer or better (I plan to put a prominent search bar on the Concept page), it's a significant shortcoming right now.

• Is there a way to add MediaWiki-like <ref> tags? Or is there some preferred alternative way to add references on wiki-tag pages?

Unfortunately not currently but we get a lot of questions about footnotes and references, so I'm personally voting on the team that we actually implement something good here.

Thanks for asking, sorry we haven't got all the things fleshed out yet, but thanks for your interest!

I didn't read enough of Burtt's book or even the chapter to judge the question, it's possible he treats motivation as foundation, possible this part wasn't a claim about a foundation. I do suspect he isn't using the word "foundation" the way you are. At least, maybe Kepler regarded his theology as of the same type as you're treating Einstein, i.e., foundation is a subjective belief? The things we'd know if we read the book. :P

<3

I think a good option here is to take the core idea of the post and make its own wiki page for it (we hope to shortly make wiki-page creation straightforward, for now it's fine to treat tag pages as wikis even when you don't want the tags).

This might be unconventional in the sense that wikis generally are more for "established" facts, but I think a wiki where people are fleshing out thoughts would be cool and good, definitely worth people trying.

That seems right to me.

Nice tag!

Seems good, I did it.

Possibly? I'm not sure if that's helpful or not. I think if there's a description for this wiki-tag, it should mention Inadequate Equilibria as a major resource.

Woop!

Sorry, should have put my Calendly link in the post.

Under our never-that-clear frontpage guidelines, community/meet-up stuff like this doesn't fit. It's possible it should/should've been. Sorry if you wanted to see it but didn't till now!