Having lost the true knowledge of reality that he possessed in the Spirit, but nonetheless needing knowledge, fallen man ends up replacing this knowledge not by another single knowledge, but by a multitude of forms of knowledge of all sorts, corresponding to the multitude of appearances among which he henceforth moves. St Mark the Ascetic thus notes that its ignorance and forgetfulness of God “cast a pall of terrible and unstable curiosity over the soul.”
But the types of knowledge resulting from this loss are partial, shifting, differing, even opposed to one another–just like the phenomenal realities to which they apply. Man, in his substitutive forms of knowledge, is limited to classifying the appearances of things–these appearances that per se have no objectivity–since they are defined by the deformed and fallen intellect of their observer.
…Fallen man’s various forms of knowledge are thus nothing more than illusory projections of his fallen consciousness, and even where an objectivity or truth seems to have been attained (such as in scientific knowledge), this objectivity and truth can be reduced as a matter of fact to the temporary agreement of states of consciousness producing the same type of projection and being in accordance with one another in some way in their common state of decline.
~Dr Jean-Claude Larchet (Therapy of Spiritual Illnesses vol.1, pp.61-62)
Prayerful Life 