Since the renaissance, we have seen a division between ordinary knowledge and scientific knowledge, which has widened its gap the more time has passed. As long as humans were not included as a part of the scientific description of the world, a rivalry did not arise between the two understandings of the world, which Wilfrid Sellars has called the manifest image and the scientific image. But after humans entered as the object of scientific description in evolutionary biology, physiology and psychology, a heated discussion has erupted among philosophers and scientists about which of these two images, if any of them, is the fundamental one. In this introductory chapter, the scientific image is identified with the use of quantitative statements, whereas the manifest image is characterized by using qualitative statements. I also argue that only because these two images see themselves as exhaustive descriptions are they perceived as competing alternatives. In fact, each of them provides an incomplete description of “man-in-the-world”, whereas together they exhaust what can be said about humans in the world.