Introduction

This volume is a brief for a specific take on the general framework of quantum mechanics. In terms of the usual partisan labels, it is an informational interpretation in which the status of the state vector is epistemic rather than ontic. On the ontic view, state vectors represent what is ultimately real in the quantum world; on the epistemic view, they are auxiliary quantities for assigning probabilities to values of observables in a world in which it is impossible to do so simultaneously for all observables. Such labels, however, are of limited use for a classification of interpretations of quantum mechanics.