This paper offers a novel interpretation of the nature and role of logical (logikôs) argumentation in Aristotle’s natural philosophy. In contrast to the standard domain interpretation, which makes logikôs argumentation the contrary of phusikôs, relying on principles drawn from outside the domain of natural science, I propose that the essential or defining feature of logikôs argumentation is the use of principles that are general relative to the question under investigation. My interpretation is developed and illustrated with a close textual analysis of Aristotle’s explanation of mule sterility in Generation of Animals II 8.

This paper provides a sustained investigation into ancient teichopolitics – the politics of constructing walls – and the question of whether the best city should be surrounded by walls. Plato’s Laws adopts the Spartan view that walls have a negative effect on national character and argues that they should be ‘left lying asleep and undisturbed in the ground’ (Leg. 6.778d). Aristotle’s Politics puts forward a series of objections to Plato and adopts the more pragmatic view that walls are necessary. Although both philosophers debate the status of walls and foreigners within the best city, they fail to draw the thoroughly modern connection between teichopolitics and immigration.