The single framework rule itself lies at the center of a large number of objections to the histories approach, which is hardly surprising since in an important sense it marks the boundary between classical and quantum physics. As it is absent from classical physics and from most quantum textbooks, the concept is unfamiliar, and one has to work through various examples in order to gain an intuitive as well as a formal understanding of how it deals with the various paradoxes and other conceptual difficulties of quantum theory. The four principles R1 to R4 found in subsection 5.1 should help in understanding how frameworks should be thought of and how they should be used. It is of particular importance that the single framework rule does not imply that there is only one way available to the physicist to think about or discuss a particular situation. What it forbids is not the construction of many, perhaps mutually incompatible, frameworks, but combining them in the fashion characteristic of the incompatibility paradoxes discussed above in subsection 10.3. Indeed, the single framework rule rather than being a restriction actually extends the Liberty of the theoretical physicist to describe the quantum world in a consistent way without the danger of running into insoluble paradoxes. But Liberty is coupled to a denial of the unicity of the world, subsection 11.4, which is perhaps the most important philosophical implication of quantum mechanics from the histories perspective, as well as the principal stumbling block in the way of a wider acceptance of that approach as a satisfactory interpretation of quantum theory.