In the beginning, they were one. As the social division of labour accelerated and knowledge advanced, philosophy and science diverged further and further from each other, bringing us to the situation today. All disciplines proliferate into sub-disciplines of sub-disciplines. We know more and more about less and less. Who sees the whole picture? The lecture will sketch the historical trajectory of intellectual specialisation, its advantages and its disadvantages. It will focus particularly on the need of science for philosophy and the consequences of lack of philosophical grounding for science.