  A property (value of an observable) might be ontologically context-dependent in the sense that in order for it to be well-defined the specification of the observable it ‘comes from’ is necessary. Thus, in order to construct a well-defined observable from operator f(Q) = g(P), we need to know whether it is physically realized via observable P or observable Q. This way out of the KS problem, was first noted (but not advocated) by van Fraassen (1973). There are, then, as many observables and kinds of physical properties for an operator f(Q) as there are ways to construct f(Q) from maximal operators. Without further explanation, however, this idea just amounts to an ad hoc proliferation of physical magnitudes. A defender of ontological contextuality certainly owes us a more explicit story about the dependence of observable f(Q) on observable Q. Two possibilities come to mind: