At each stage man has to abandon the secure, the trusted, and —for his present moment— the ultimate. At each stage he has to struggle with the denying force of inertia. He has to surmount a mental obstacle as once he had to surmount biological obstacles.
If he succeeds, he learns more, understands more, gets closer and closer to participating. It may be that he is now required to confront —and accept— the mechanism of his own evolution."