"Before Greece the domain of the intellect belonged to the priests. They were the intellectual class of Egypt. Their power was tremendous. Kings were subject to it. Great men must have built up that mighty organization, great minds, keen intellects, but what they learned of old truth and what they discovered of new truth was valued as it increased the prestige of the organization. And since Truth is a jealous mistress and will reveal herself not a whit to any but a disinterested seeker, as the power of the priesthood grew and any idea that tended to weaken it met with a cold reception, the priests must fairly soon have become sorry intellectualists, guardians only of what seekers of old had found, never using their own minds with freedom.
There was another result no less inevitable: all they knew must be kept jealously within the organization. To teach the people so that they would begin to think for themselves, would be to destroy the surest prop of their power. No one except
themselves must have knowledge, for to be ignorant is to be afraid, and in the dark mystery of the unknown a man cannot find his way alone. He must have guides to speak to him with authority. Ignorance was the foundation upon which the priest power rested. In truth, the two, the mystery and those who dealt in it, reinforced each other in such sort that each appears both the cause and the effect of the other. The power of the priest depended upon the darkness of the mystery; his effort must ever be directed toward increasing it and opposing any attempt to throw light upon it."

The Greek Way Edith Hamilton