  Essential elements of quantum theory are derived from an epistemic point of
view, i.e., the viewpoint that thetheory has to do with what can be said about
nature. This gives a relationship to statistical reasoning and to other areas
of modelling and decision making. In particular, a quantum state can be defined
from an epistemic point of view to consist of two elements: A (maximal)
question about the value of some parameter together with the answer to that
question. Quantization itself can be approached from the point of view of model
reduction under symmetry.
