Scientific realism asserts that the methods of science, combined with the intellectual powers of human beings can give us reliable knowledge of states of the world beyond the limits of perception. Among the varieties of realism, policy realism is based on the principle that taking plausible theories to be putative descriptions of actual states of affairs is the best way to design experiments and to advance our knowledge. We carve out the umwelt from the welt by the use of our instruments and apparatus. The key procedure in science has been and still is the invention and testing of models---plausibility and empirical adequacy are the marks of a theory based on a model capable of supporting policy realism