On traditional theism, God is not only a creator but also a conserver. The doctrine of conservation, however, appears to face a dilemma. Either conservation is continuous re-creation with consequences inimical to diachronic identity, or conservation is an operation upon a pre-existent entity, which, because it is pre-existent, is in no clear need of conservation. This article first makes a case for the dilemma, and then proposes a way between its horns. Safe passage is possible if we adopt presentist four-dimensionalism, i.e. the conjunction of presentism, according to which temporally present items alone exist, and four-dimensionalism, the doctrine that individuals are not continuants but wholes of temporal parts.

This article responds to Quentin Smith's, ‘The Reason the Universe Exists is that it Caused Itself to Exist’, Philosophy74 (1999), 579–586. My rejoinder makes three main points. The first is that Smith's argument for a finitely old, but causally self-explanatory, universe fails from probative overkill: if sound, it also shows that all manner of paltry event-sequences are causally self-explanatory.The second point is that the refutation of Smith's argument extends to Hume's argument for an infinitely old causally self-explanatory universe, as well as to Smith's two ‘causal loop’ arguments. The problem with all four arguments is their reliance on Hume's principle that to explain the members of a collection is ipso facto to explain the collection. This principle succumbs to counterexamples. The third point is that, even if Hume's principle were true, Smith's argument could not succeed without the aid of a theory of causation according to which causation is production (causation of existence).

The doctrine that there are no logically necessary connections in nature can be used to support both occasionalism, according to which God alone can be a cause, and ‘anti-occasionalism’, according to which God cannot be a cause. Quentin Smith has recently invoked the ‘no logically necessary connections in nature’ doctrine in support of the latter. I bring two main objections against his thesis that God (logically) cannot be a cause. The first is that there are good reasons to think that there are irreducible dispositions in nature, and that where such dispositions are manifested, there are logically necessary causal connections. The second objection is that even if the ‘no logically necessary connections in nature’ doctrine is true, one is not forced to deny causal efficacy to God: with no breach in logical propriety, one may embrace occasionalism.

Suppose we say that a deductive argument is probative just in case it is (i) valid in point of logical form, (ii) possesses true premises, and (iii) is free of informal fallacy. We can then say that an argument is normatively persuasive for a person if and only if it is both probative and has premises that can be accepted, without any breach of epistemic propriety, by the person in question. If the premises of a probative argument would be accepted by any reasonable person, I will call such an argument demonstrative.