Miller's formulation of problems was controlled by tensions between conscious" and "mechanical" and between "understanding" and "mystery." The mechanical world, devoid of morality and purpose, was incompatible with conscious beauty and ethics; within the "conscious" the optimistic drive for knowledge about an intelligible universe conflicted with belief in an unknowable, awful universe. Miller's history was also informed by his sense of development: history proceeds in a continuing series of interactions between inherited cultural forms, and immediate environmental circumstances. Culture is never merely the "product" of environment, but an active agent in the interaction. The search for "historical knowledge" itself proceeds on the terms of this interaction. Here Miller rejected both positivism and the capricious relativism of Becker for the harder relativism subsequently articulated by Kuhn and Toulmin: "forms" are neither wholly arbitrary nor entirely discovered in "the facts," but are instead the inheritance and creation of the historian, altered and confirmed by his experience.