I actually just sat down to crack open MITs Theory of Knowledge and it seems promising and free: https://ocw.mit.edu/courses/24-211-theory-of-knowledge-sprin...

This also looks promising:

https://hiw.kuleuven.be/en/study/prospective/OOCP/introducti...

If you wanted something a bit different Wittgenstein’s Tractatus has always made my head spin with possibilities:

https://people.umass.edu/klement/tlp/tlp-hyperlinked.html