Pace Dilthey, Plessner's "Levels" is not about interpreting historical contingencies, nor about the more familiar evolutionary sedimentation of frozen accidents, but rather is about looking to establish transcendental conditions (or categories) of biotic possibility that he refers to as "modals of the organic." As with Hegel he challenges us with a proposed logic of life always mobilized by dialectical tensions, albeit not on the basis of any form of idealism and bereft of a Hollywood ending. For Plessner, that which is both the sine qua non of the living state and that generative 'principle' from which organic modals can be derived is the on-going performance of a self-positioning boundary, and it is highly unlikely that anybody has ever thought as deeply about the implications of what this means.