Is psychoanalysis a science? This question has been discussed for a long time. Browsing in the contemporary philosophy of science, especially the works concerned with the exact sciences, proves to be very instructive. First it becomes clear that one cannot find one point of view that can make one decide unreservedly that psychoanalysis is not a science. Secondly, and this is even more important, we soon realise how widely divergent the philosophical views are on what constitutes a science. This is documented in a survey of the following tendenties in contemporary philosophy of science: inductivism, logical empirism and the points of view of outstanding philosophers as: Popper, Kuhn, Lakatos and Feyerabend. Some points of particular interest are discussed focusing upon Freud's 'Interpretation of dreams'. From the previous discussion follows the conclusion that those concerned with psychoanalysis should not be so much afraid that they are in the dark, where Science's divine light does not shine, and that those who reject psychoanalysis as being unscientific, should realise they have not a solid philosophical backing behind them. Finally it is pointed out that going into philosophy of science is also of a more general interest, since it could protect one against taking for granted so much that seems to be based on scientific grounds and since it could dissuade many researchera from research-work, seemingly undertaken according to the principles of scientific methodology, but proving to be of poor value on broader philosophical examinations.