A famous German-language book on philosophy first published in 1929 has finally been translated into English. The work is Helmuth Plessner's LEVELS OF ORGANIC LIFE AND THE HUMAN. For Plessner what is critical to grasp about life, the sine qua non of the living, is that every organism has a self-positioning boundary. There is the organism on the one hand, there is the environment on the other. Further, the organism itself is largely responsible for where that boundary is. Animals move about more than plants of course, but the difference is of degree rather than kind, and all organisms grow. The outer boundary itself may be defined as that which is neither living nor non-living (the outer layer of our skin consists of dead cells), this making it a liminal zone. There is movement both outward and inward. The liminal zone moves outward as an organism grows, there is movement inward in the process of digestion. In Plessner's words, "It is these two moments togethe...
