 Despite rearguard defenses by the Romantics, Newtonian physics appeared to show that empirical reality fits classical logic. The hard sciences illustrated the crystalline growth of determinacy. But in a shocking reversal, quantum mechanics suggests the possibility of reversing from determinacy to indeterminacy. What had been formerly regarded as determinate, the position and velocity of an object, was regarded as indeterminate by Werner Heisenberg. Quantum logicians, such as Hillary Putnam (1976), abandoned the distributive laws of propositional logic. 