peaked on a particular state $\rho_{D_K}$ dictated by the measurement results, regardless of the prior probability $P(\rho)$, as long as $P(\rho)$ is nonzero in a neighbourhood of $\rho_{D_K}$”[^15] This result can be used to account for the fact that the states assigned by different agents will converge after a sufficiently large number of measurements witnessed without postulating that there is any such thing as the agent-independent unknown *true* quantum state the states assigned by the different agents converge to. As this shows, taking seriously quantum theoretical practice inasmuch as it involves talk about “unknown quantum states” does not mean that one has to embrace an ontic account of quantum states, in which such talk is interpreted literally.

In order to be consistent as fully-fledged subjective Bayesian interpretation of quantum probabilities, quantum Bayesianism goes very far in interpreting elements of the quantum mechanical formalism as subjective. The view is particularly radical in its rejection of the innocently looking assumption that there can be an objective matter as to which observable some numerical value obtained in an experiment is a value of. To put it differently, quantum Bayesianism rejects the idea that the question of which observable is measured in which experimental 