According to truthmaker necessitarianism, the existence of the truthmaker necessitates the truth of the sentence: any possible world in which the truthmaker exists is a world in which the sentence is true. Truthmaker necessitarianism is automatic on the necessitation analysis of truthmaking. On a grounding account, truthmaker necessitarianism can be upheld by endorsing an axiomatic constraint on the notion of grounding: if an entity grounds the truth of a sentence, then, necessarily, if the entity exists, then the sentence is true. The problems to be discussed (in §3.3 and §3.4) apply to any truthmaker account of ontological commitment that endorses truthmaker necessitarianism.[31]