Nature attains perfection, but man never does. There is a perfect ant, a perfect bee, but man is perpetually unfinished. He is both an unfinished animal and an unfinished man. It is this incurable unfinishedness which sets man apart from other living things. For, in the attempt to finish himself, man becomes a creator. Moreover, the incurable unfinishedness keeps man perpetually immature, perpetually capable of learning and growing.