 A third worry, which applies to all (restricted or unrestricted) composition principles, is this. Mereology is supposed to be ontologically “neutral”. But it is a fact that the models of a theory cum composition principles tend to be more densely populated than those of the corresponding composition-free theories. If the ontological commitment of a theory is measured in Quinean terms—via the dictum “to be is to be a value of a bound variable” (1939: 708)—it follows that such theories involve greater ontological commitments than their composition-free counterparts. This is particularly worrying in the absence of the Strong Supplementation postulate (P.5)—hence the extensionality principle (27)—for then the ontological exuberance of such theories may yield massive multiplication. But the worry is a general one: composition, whether restricted or unrestricted, is not an ontologically “innocent” operation.