Other than PhD students at universities (undergrads are often just there for the degree), I'd recommend https://www.lesswrong.com/ https://www.lesswrong.com/ ,

Other than PhD students at universities (undergrads are often just there for the degree), I'd recommend https://www.lesswrong.com/ https://www.lesswrong.com/ , certain subreddits, MOOC platforms like Coursera or EdX, and here on Hacker News (this very thread actually spawned a discourse group: https://discord.gg/WyRBDGgeCG https://discord.gg/WyRBDGgeCG ) A simple heuristic: search for submissions about Zettelkasten, Evergreen notes, spaced repetition, and similar knowledge organization or learning methodologies and tools (Roam Research, Notion, Obsidian, Anki, etc). If someone is sufficiently motivated to write down and study new things they encounter, it's likely that they seriously love to learn. https://hn.algolia.com/?dateRange=all&query=Zettelkasten&sort=byPopularity&type=story https://hn.algolia.com/?dateRange=all&query=Zettelkasten&sor... https://hn.algolia.com/?dateRange=all&query=Anki&sort=byPopularity&type=story https://hn.algolia.com/?dateRange=all&query=Anki&sort=byPopu... https://notes.andymatuschak.org/Evergreen_notes https://notes.andymatuschak.org/Evergreen_notes https://www.reddit.com/r/NoteTaking/#sort=top;t=month https://www.reddit.com/r/NoteTaking/#sort=top;t=month Certain topics have very vibrant communities and forums, eg: language learning on Reddit, the Busuu community, or HiNative. Also, consider taking a philosophy (theory of knowledge) class either at a local university or community college if available, or on a MOOC like Coursera or EdX. You might find many intellectually curious people there.