In 1997 at the Great Blissful Vajra seminar, Rinpoche elucidates as a supplementary topic to the path of special skills, the nature of the four states, when they involve delusion and when not, the stages of the path; the means for binding them, and their resultant four kayas.
This is talk 14 of 16. You can search for example "Karmê Chöling 97" for the remaining talks.
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