This is a lecture, which explains the informal language and sketchiness of the text. The paper deals with the idea of hermeneutics from the viewpoint of practical biology and cognitive science. This requires some clarification. Traditionally, the above mentioned disciplines, like many others, utilize little more than basic empiry and computational modeling. Philosophy is seldom cited, if ever; in particular, hermeneutics enters virtually nowhere except, perhaps, in the study of the making of biology. What the present paper suggests is something very different in spirit, namely, that hermeneutic concepts should play an important role in biology proper. The hypothesis is that hermeneutics should appear not just as a study tool of, but in biology. What will be outlined below is not the first presentation of this idea: the basic material comes from two earlier publications, a book devoted entirely to related topics in English and a casual essay in Hungarian [Kampis 1991a, Kampis 1992b].