As it happens, the Luke-Yoda phraseology like "Do or do not. There is no try" seems to be drawn by George Lucas from the popular late 1960s era books by Carlos Castaneda about a mentorship (~7 mil copies sold). That in turn seems to be about the apprenticeship that Castaneda had with his UCLA PhD advisor Harold Garfinkel:

Parallel Yoda quotes: https://books.google.com/books?id=pAjYCgAAQBAJ&pg=PT47#v=one... via: https://www.slate.com/articles/arts/cover_story/2015/12/star...

Thread with 1975 magazine explanation of Castaneda's advisor found partly via David Chapman: https://twitter.com/thadk/status/1670316860368199681?s=20