No, and that’s ok. Here’s why. All knowledge consists of no-centered ontologies. It’s just a web of connections, connotations, denotations, and annotations.
Humans construct hierarchical or centering approaches to help them approach knowledge from one perspective or another. The downside to these approaches i s that over time, they change.
The genius of Obsidian is it lets you handle both sides of this tension. You can easily craft hierarchies or centers of knowledge that let you organize knowledge one way now. You can even organizes knowledge multiple ways at one time.
Later, as your approach and perspective evolves, Obsidian makes it easy to adjust connections and hierarchies and centers to reflect new ways of thinking.
That said some broad hierarchy makes Obsidian a little easier, so use folders. Err on fewer folders than more.
You can make weak connections with tags (all things with this tag may be related) and strong connections with actual links (these linked items have a strong connection).
MOCs let you create a center or “top-level” node you can use to drive hierarchies. For example, for periodic notes, I have year notes that link to month notes that link to week notes that link to daily notes.
For projects, I have a project note that links to project reference notes and to project meeting notes.
For organizations, I have org notes that link to people and project notes. Each of these hierarchies helps me traverse a hierarchy to explore more and more detailed information as I wor down the “tree”.
Like with folders and tags, link less where you know it’s a crucial link and add more links as necessary.
