This chapter attends to the prescribed procedures for relating one to multiple and multiplicity in Badiou's and Deleuze's work. I begin with the work of constructing consistent multiples in Badiou's work, a procedure requiring attention to the void set and its mark Ø, their background in Zermelo and Bourbaki, and axioms of Zermelo-Fraenkel set theory. I attend to this procedure's relation to Badiou's earlier account of scission, a technique for "cutting" a one from the multiple. I address one-production in Deleuze's account by discussing the differential relation (dy/dx) and its mobilization toward the pre-individual singularity, which Deleuze develops in his account of the virtual idea. My analysis focuses on those procedures by which the relation of one to multiple is maintained, namely subtraction, apparent in the analysis of the war machine in A Thousand Plateaus and in their assessment of the cogito in "Example 1". I show how Deleuze's earlier concern with overturned Platonism expresses this subtractive impulse; in short, one sees that where multiplicity appears in Deleuze's oeuvre, subtraction seems to follow.