Progress of Theory in the Last Century B.C.

^{§ 1} . The various tendencies toward a mystical Pythagorism which developed among the followers of the Academy proved unsatisfactory. As a consequence metaphysical speculation languishes and attempts are made to develop the ethical side of Platonism or supply its deficiencies in the sphere of science. This involves abandoning the pure reason and considering the significance of those faculties which come lower on the psychic scale. Of these it is Belief (πίστις) that actually attracts attention. The problem for solution is restated in the form “how can man attain the certainty which he requires for the practical life?”