The bio-ethical debate on PGD and embryonie stem-cell research is characterized by many paradoxes, regarding the moral status of earliest human life between ›nature‹ and ›subjectivity‹ . The ›conditio humana‹ , however, is not defined by biological features. As a cultural factor, it focuses on the self-realization of the subject in contexts of social acknowledgement. Against this background, the article deals with the anthropological metaphor of the image-of-god and its peculiar character of not being an image. This allows us to explain a ›negative‹ concept of anthropology, analogaus to the dialectical model of ›docta ignorantia‹ . On the one hand, this concept of a human being avoids a definition of its very beginning as coming tagether of ›nature‹ and ›subjectivity‹ , whereas, on the other hand, the absolute dignity of the human is emphasized. By this line of thought some argurnents are clarified, which have arisen in the bioethical debate for and against PGD and stern-cell research.