  Contemporary scientific perspectivism is re-evaluated and extended to a
comprehensive perspectivist methodology and 'mediated' realistic epistemology,
especially, with reference to quantum mechanics. In the present study, this is
realized by representing categorically the global structure of a quantum
algebra of events in terms of structured multitudes of interrelated local
Boolean frames, realized as suitable perspectives or contexts for measuring
physical quantities. The philosophical meaning of the proposed approach implies
that the quantum world can be consistently approached and comprehended through
a multilevel structure of locally variable perspectives, which interlock, in a
category-theoretical environment, to form a coherent picture of the whole in a
nontrivial way. Thus, in contrast to a panoptical "view from nowhere" of the
classical paradigm, quantum theory acknowledges in an essential way a
perspectival/contextual character of scientific knowledge.
