This paper relates the concept of relevance to its biological foundations by combining Alfred Schutz’s social phenomenology and Helmuth Plessner’s theory of organic life and philosophical anthropology. Relevance interlinks human sign use with the human “lifeworld” (Husserl) as a whole. The biological foundations of relevance, in turn, interlink that lifeworld with the “world of life” that includes us among other lifeforms. I analyze human relevance as an interplay of two tendencies, termed “closedness” and “openness,” that underlies our production of “meaning” (...) (Schutz). Relevance in this general sense involves not only the mind, but also the body of homo sapiens. To provide a unified theoretical framework, I reconstruct Plessner’s “philosophical biology.” According to Plessner, organic life consists in a tension between closedness and openness. This tension unfolds through the “levels” of plants, animals, and humans. Plessner’s analysis of humans as “excentric” animals helps explain the two tendencies that drive human relevance and distinguish our experience from that of our closest animal relatives. At the same time, Plessner traces a robust continuity between us and other lifeforms. The human “level” merely makes “explicit” certain elements (including the Cartesian distinction between “mind” and “body”) that all organisms implicitly possess. (shrink)