Abstract
The article explores the relationship between Locke and Leibniz's account of space and how this impacts on their understanding of possibility, and particularly practical choices between possibilities within a modal space. Using Borges' short story 'Pierre Menard, author of the Quixote' it argues that Locke's acquiescence to absolute space severely restricts his account of the power to do things. Leibniz's retention of relative space permits a much richer account of possible, yet he binds these worlds together under a universal set of principles which are morally true in every possible world. He calls these morally impossible (prohibited), echoing the Scholastic language of repugnance. 'Menard' is employed to critique this resort to universality, before an alternative possible truth structure is sketched as a response to the 'self-evident' truths defended by Leibniz.