I thought of Descartes' Meditations (where he argues subject as rational being, as in cogito ergo sum) and Plato's Republic (which includes the infamous allegory of the cave) as well
I think the implicit suggestion on the necessity for God (for cogito to exist, according to Descartes) and some other problematic sides to his 'rationalist' thinking would not be in agreement with the overall island mythology or feel or spirit...and consequently not all too influential on Ben's thought... Plato's Republic is an another key text, in so far as being about a political utopia, but Plato's vision is quite anti-free will and definitely anti-democratic- I can see both Alpert and Dharma guys being quite critical of it. Still, can't see how Ben would miss reading it... among the classics for all the book-warms, especially for those with leadership skills
Aristotle works would probably take about 1200-1500 pages of total (Metaphysics is about some 400 pages, on its own). Having read quite a decent portion of that for my grad studies, I am only hoping Ben haven't gone through all of it- if he did, then we have a perfectly reasonable explanation for his talking to an 'empty' rocking chair. Add the Kant and Hegel mentioned, I wonder why he didn't figure the dynamites before Rousseau.. A few years back, I wished I had some