Whenever a person strives, by the help of dialectic, to start in pursuit of every reality by a simple process of reason, independent of all sensuous information - never flinching, until by an act of the pure intelligence he has grasped the real nature of good - he arrives at the very end of the intellectual world.
PlatoThe ultimate design of the Mysteries ... was to lead us back to the principles from which we descended, ... a perfect enjoyment of intellectual [spiritual] good.
Plato