On the epistemology of inspiration and intuition; 4 criteria of human knowledge: sense perception, intellect, scriptural tradition, and inspiration. Abdu'l-Bahá adds a fifth: the inmost heart.
The Criteria of Knowledge:
published in Studies in Bahá'í Philosophy
, vols. 2-3, pages 37-58
Idyllwild, CA: Charles Schlacks, 2014