"It has been a continuing theme of this book that our commitment to any approach to the problems of existence (the overcoming of the world, the humanization of the world, and the struggle with the world first among them) can enjoy no definitive justification. Its demands always exceed, immeasurably, its grounds for making them. It says, “Follow me.” It can never give a conclusive reason to do so. All that it can do is to make an incomplete argument and a defeasible appeal. It cannot escape the circularity in all our large-scale transformative projects: for better or worse, each of them is a partly self-fulfilling prophecy. If it is embraced and it works, it remakes part of experience in its image."