Schopenhauer, Über die vierfache Wurzel des Satzes vom zureichenden Grunde (1813), sec. 20:
. . . causa prima ist, eben so gut wie causa sui, eine contradictio in adjecto, obschon der erstere Ausdruck viel häufiger gebraucht wird, als der letztere, und auch mit ganz ernsthafter, sogar feierlicher Miene ausgesprochen zu werden pflegt, ja Manche, insonderheit Englische Reverends, recht erbaulich die Augen verdrehn, wenn sie, mit Emphase und Rührung, the first cause, — diese contradictio in adjecto, — aussprechen. Sie wissen es: eine erste Ursache ist gerade und genau so undenkbar, wie die Stelle, wo der Raum ein Ende hat, oder der Augenblick, da die Zeit einen Anfang nahm. Denn jede Ursache ist eine Veränderung, bei der man nach der ihr vorhergegangenen Veränderung, durch die sie herbeigeführt worden, notwendig fragen muß, und so in infinitum, in infinitum!
I quote this passage in German because I do not have the English at hand, but also because the pessimist's German is very beautiful and very clear, and closer to English than any other philosophical German I have ever read.
Schopenhauer's claim is that a first cause (causa prima) is unthinkable (undenkbar) because every cause is an alteration (Veränderung) which follows upon a preceding alteration. For if every cause is an alteration that follows upon a preceding alteration, then the series of causes is infinite in the past direction, and there is no temporally first cause.
And so 'first cause' is a contradictio in adiecto: the adjective 'first' contradicts the noun 'cause.' Charitably interpreted, however, Schopenhauer is not making a semantic point about word meanings. What he really wants to say is that the essence of causation is such as to disallow both a temporally first cause and a logically/metaphysically first cause. There cannot be a temporally first cause because every cause is an alteration that follows upon a preceding alteration. And there cannot be a logically/metaphysically first cause for the same reason: if every cause and effect is an alteration in a substance then no substance can be a cause or an effect. Causation is always and everywhere the causation of alterations in existing things by alterations in other existing things; it is never the causation of the existing of things. For Schopenhauer, as I read him, the ultimate substrates of alterational change lie one and all outside the causal nexus. If so, there cannot be a causal explanation of the sheer existence of the world.
Here I impute to Schopenhauer the following argument:
1. The relata of the causal relation are changes.
2. Every change is an alteration.
3. Every alteration presupposes a substrate of alteration that does not change in respect of its existence and identity.
4. Some, but not all, substrates of alteration are non-ultimate, where a non-ultimate substrate is one whose coming into existence or passing out of existence is reducible to the alteration of an already existing substrate or substrates; hence there must be ultimate substrates of alteration.
5. If there are ultimate substrates of alteration, then they do not come into existence or pass away.
6. Because changes occur, there are ultimate substrates of alteration.
7. There are ultimate substrates of change that do not come into existence or pass away, and are thus sempiternal. (5, 6)
8. The existence of these sempiternal substrata are at the basis of all causation.
9. The existence of the ultimate substrata of change cannot have a cause, divine or otherwise.
10. Cosmological arguments, presupposing as they do that causation of existence makes sense, are one and all unsound.
What can we say in critique of this argument? (2) may be questioned. If every change is an alteration, then nothing can come into existence except by the alteration of some thing or things already in existence. That implies that there cannot be creation ex nihilo. But then Schopenhauer's argument may be said to beg the question against the theist at line (2) -- unless there is some independent way of supporting (2).
But is creation ex nihilo a change? In what? It cannot be a change in some stuff out of which God creates. For then the creation would not be ex nihilo. God is not a demiurge. Nor can it be a real change in God if God is unchanging. One might just say that the creation out of nothing of contingent beings is a change in the way things are. But this is tricky because this change would appear to have to be an atemporal change. There could be time without change, but how could there be change without time?
Consider the possible worlds in which no contingent beings exist and compare them with C, a world in which contingent beings exist. Suppose God causes C to be actual. Suppose further that C -- like all worlds -- is a maximal Fregean proposition or a maximal Chisholmian state of affairs. Now we have a substrate of exnihilation, namely, the the maximal proposition or state of affairs C. It is not that C is created, but that C is made actual. But it is not as if C 'goes' from being unactual to being actual. 'Going' is a transition, and transition takes time, and indeed time as involving temporal becoming. Given that time is contingent, there is no time at which there are no contingent beings and a later time at which there are. Divine creation is presumably not in time, but of time and of everything else that is contingent.
Well, perhaps we could introduce a notion of modal change which would be analogous to temporal change as the latter is construed by B-theorists:
Reality changes just in case it has different properties in different possible worlds.
Reality changes from not containing contingent beings to containing them iff there are possible worlds in which there are, and possible worlds in which there are not, contingent beings.
If every change requires a cause, then presumably the change just mentioned requires a divine cause.
To review the dialectic: if creatures are effects of a cause, and effects are changes, and every change requires a substrate, then what is the subject or substrate of exhihilation? What is creatio ex nihilo a change in? My very tentative suggestion is that it is a change in reality in accordance with the definitions just given.
Since the cause of this change cannot itself be a change, (1) must be rejected as well.