Drawing the Limits of Knowledge
Metaphysicians hold that there are two kinds of real things: those that are truly real and those that are less real. The former are the grounds of the latter. Metaphysics is supposed to be knowledge of the truly real things; the reality that underlies appearances. Schlick argued (i) that metaphysics so understood needs to have a special source of knowledge distinct from the sources of knowledge on which science and common sense rely and (ii) that there is no such source of knowledge. Hence, even if there are truly real objects and facts, they are beyond the limits of knowledge. Schlick concludes that there are no differences in degrees of being: all being is on a par. The chapter gives an overview of the metaphysicians attacked by Schlick and reconstructs his argument against metaphysical knowledge that is based on the two-term view of cognition.