The question of the division of the speculative sciences enjoys a long and rich tradition, dating back to the time of Plato and Aristotle. It is important in order to get a picture of the different types of knowledge, the relationship between them, their specificity with regard to the object and method proper to them. It is particularly important in order to find the proper status of metaphysical science with respect to the other two speculative sciences: physics and mathematics. In the seminar we will try to make an historical path, through the texts of the most significant authors, analyzing the proposals made and the criteria followed to establish the division of the speculative sciences, from Plato to our days. Finally we will try to enter in the merit of the debate on the so-called “degrees of abstraction” and the validity of this proposal.