KANT lettre a marcus herz

n his letter to Marcus Herz of February 21, 1772, Immanuel Kant announces his discovery of "the key to the whole secret of the as yet still hidden metaphysics" (10:130). This is the question "how my understanding is supposed to form concepts of objects, themselves completely a priori, with which necessarily the things are supposed to agree" (10:131). Kant goes on to dismiss two possible answers to this question: the theory of hyperphysical influence, which he ascribes to Nicolas Malebranche (and to Plato), and the theory of pre-established intellectual harmony, which he ascribes to Christian August Crusius. Against these theories he objects that "the deus ex machina is the most inconsistent thing to choose in the determination of the origin and the validity of our cognitions" (10:131), which has "besides the deceptive circle in the chain of our cognitions, also the disadvantage that it encourages every whim or reverent or brooding fantasy" (10:131).