The Mathematics of Novelty: Badiou’s Minimalist Metaphysics tackles the issue of philosophical materialism in Gilles Deleuze and Alain Badiou, enquiring after the source and nature of the ‘novelty’ that both philosophers of multiplicity claim to discover in the objective world. In this characteristically erudite analysis, Sam Gillespie maintains that where novelty in Deleuze is ultimately located in a Leibnizian affirmation of the world, for Badiou, the new, which is the coming-to-be of a truth, must be located exterior to the ‘situation’, i.e. in the void. Following a lucid presentation of the central concepts of Badiou’s philosophy as they relate to the problem of novelty (mathematics as ontology, truth, the subject and the event), Gillespie identifies a significant problem in Badiou’s conception of the subject which he suggests can be answered by way of a supplementary framework derived from Lacan’s concept of anxiety. Gillespie’s intent to illuminate the relation of philosophy to the four truth procedures (art, love, science, politics) leads him to the polemical conclusion that, as a transformative rather than descriptive or reflective project, Badiou’s philosophy ultimately reclaims the power of the negative from the positivity and pure productiveness of Deleuze’s system, thereby freeing thought from the limits set by experience.