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AbstractElay Shech and John Earman have recently argued that the common topological interpretation of the Aharonov–Bohm (AB) effect is unsatisfactory because it fails to justify idealizations that it presupposes. In particular, they argue that an adequate account of the AB effect must address the role of boundary conditions in certain ideal cases of the effect. In this paper I defend the topological interpretation against their criticisms. I consider three types of idealization that might arise in treatments of the effect. First, Shech takes the AB effect to involve an idealization in the form of a singular limit, analogous to the thermodynamic limit in statistical mechanics. But, I argue, the AB effect itself features no singular limits, so it doesn't involve idealizations in this sense. Second, I argue that Shech and Earman's emphasis on the role of boundary conditions in the AB effect is misplaced. The idealizations that are useful in connecting the theoretical description of the AB effect to experiment do interact with facts about boundary conditions, but none of these idealizations are presupposed by the topological interpretation of the effect. Indeed, the boundary conditions for which Shech and demands justification are incompatible with some instances of the AB effect, so the topological interpretation ought not justify them. Finally, I address the role of the non-relativistic approximation usually presumed in discussions of the AB effect. This approximation is essential if—as the topological interpretation supposes—the AB effect constrains and justifies a relativistic theory of the electromagnetic interaction. In this case the ends justify the means. So the topological view presupposes no unjustified idealizations.

The following article responds to a realist critique of ideal theory in the "official" liberal democratic account of civil disobedience classically offered by John Rawls. The shortcomings the critical theorist, Robin Celikates (2014:236), identifies in Rawls's account follow, "at least, in part, from treating ideal theory as an independent starting point and working towards a definition of this decidedly nonideal political practice from there". The research aims, firstly, to identify and to explain a significant weakness in "new realist" political theory, and, secondly, to offer direction from our recent historical past to contemporary struggles for social justice in South Africa today, which suffer from such weakness in practice. The Freedom Charter is identified as the embodiment of a set of ethical ideals which exceeds but which may complement Tully's approach. . Mainstream historical sources are used, firstly, to identify a serious shortcoming with a dominant approach in political theory, and, secondly, to identify a significant factor that frustrates the effectiveness of "service delivery" protests today.