- Knowledge is of three kinds: (1) First: “lmul-yaqin, [knowledge by in- ference] which is akin to seeing smoke rise from a distance and deducing that there must be a fire at that spot; (2) Second: ainul-yagin [certainty by sight], which is akin to seeing that fire with one’s own eyes; and (3) Third: haqqul-yagqin, [true certainty] which is akin to feeling its heat by putting one’s hand in that fire. (Author)