A philosophical essay
An excellent online course on the mystical experience. It begins with the premise that Enlightenment is outside the scriptures. The broad range of links available on various descriptions of "Zen" experience is very useful.
An essay discussing the relation between William Blake's poetry and Zen.
An essay on how the methods of General Semantics and Zen complement one another.
A comparison of Aristotle, Nagarjuna and Bhaskar.
1913 classic book by Kaiten Nukariya. Complete online book.
A brief introduction to Zen thought.
A philosophical analysis of Zen koans by John King-Farlow.
A comparison of the Aristotilian view of truth and Zen's view.
by Peter N. Gregory, from Philosophy East and West.