We have opened an audio streaming of Rick Mansell's translation of Dr Johannes Stein's Doctoral Thesis on his Theory of Knowledge. Evidently Rudolf Steiner helped hi do this document and it is excellent in that it concentrates into words the reason for a continuing the work of nature in our spiritual development of the soul. It is the exact same foundation I use for spiritual research.
The course is very reasonable at $39 and is over 2 hours of a very dense audio presentation. A forum is provided for comments and questions!