The importance that all these Indian metaphysics (The Six Views), accord to “knowledge” is easily explained if we take into consideration the causes of human suffering. The [painful quality of an unenlightened] human life is not owing to a divine punishment or to an original sin, but to ignorance. Not any and every kind of ignorance, but only ignorance of the true nature of Spirit, the ignorance that makes us confuse Spirit with our psychomental experience, that makes us attribute “qualities” and predicates to the eternal and autonomous principle that is Spirit -- in short, a metaphysical ignorance. Hence it is natural that it should be a metaphysical knowledge that supervenes to end this ignorance. This metaphysical knowledge leads the disciple to the threshold of illumination -- that is, to the true “Self.” And it is this knowledge of one’s Self -- not in the profane sense of the term, but in its ascetic and spiritual sense -- that is the end pursued by the majority of Indian (metaphysical) systems, though each of them indicates a different way of reaching it.
Yoga, Freedom and Immortality • Mircea Eliade; Princeton U. Press; 2nd edition, 1970