[sReinwald]

I keep one vault for almost everything because the cross-domain links are where the interesting stuff happens. I studied sociology, political science, and media & communication before moving into IT, and I'm still actively interested in all of it and especially how these topics intersect. Where does a note on Baudrillard's concept of hyperreality go? The social science vault? The IT vault? Both? With a single vault I don't have to answer that question - the note exists, and I can use it to make connections to AI, social media, or cultural trends.

Multiple vaults break this. You end up duplicating notes, or linking across vault boundaries (which adds friction), or just forgetting where you put something. That's trading one of Obsidian's strongest features for... tidier folders.

The one case where I do split things out is genuinely isolated project knowledge - like a D&D campaign I used to GM. 99% of those notes have zero connection to anything else. Separation makes sense there precisely because there's nothing to link.

One more thing: a lot of people solve the "big vault gets messy" problem with elaborate folder structures, but Obsidian's search (especially with Omnisearch) makes most of that unnecessary. I don't really organize my notes into careful hierarchies. I write them, link them, and search for them. The mess is fine. I am one with the mess.

[btreecat]

I just don't see myself needing to cross link my DnD, work, food, and home-lab nots significantly enough to not use separate collections.

[sReinwald]

Yeah, totally valid for things like D&D - I split that out too, for the same reason.

Work and homelab overlap constantly for me though. I make heavy use of periodic notes, so even something like recipes would get linked in weekly logs for meal planning or tracking. The connections don't have to be deep to be useful - sometimes it might just be 'I made this thing on this day' and that's enough context to be worth having in one place.

[btreecat]

I like that because it's just text, and obsidian is un-opinionated on organization, it allows us all to find workflows that suit us!