Quantum Bayesianism makes conventional assumptions about conscious experience and the world, which are “deconstructed” here. Conscious experience is succeeded by Heideggerian Existenz as world-thrownness. But unlike Heidegger, Existenz is conceived as a monadological dis-closure in the other-tuned, self-tuned and past-tuned “between” of the quantum thermo field brain’s dual mode vacuum state. The wave function is identified with Bayesian expectation conceived as the brain’s “self-tuning” capability subject to informative modification. Physical reality is never worldly but quantum at all scales. Worlds are disclosed only in monadological parallel in the quantum brain’s tuned between. This version of Quantum Bayesianism offers a novel solution to the measurement problem.