The dispute between Hollander and Peart, and Hirsch, turns on the nature and role of verification in Mill's perception of the appropriate method for Political Economy. Professor Hirsch maintains against us that, for Mill, the models constructed by political economists are insulated from verification. His case is based on two counterclaims. First, that when Mill writes of “verification” in Book III of the Logic, he has in mind a procedure differing from that appropriate for Political Economy, which allows only “indirect verification” (outlined in Book VI). Hirsch finds that Hollander and Peart confuse the two. Secondly, since the contexts of our case studies often relate to policy formulation, Hirsch finds our elucidations of an appeal to experience of a more basic order to be unconvincing.