If everything in the universe is contingent, does it follow that the universe is contingent? No it doesn't, and to think otherwise would be to commit the fallacy of composition. If the parts of a whole have a certain property, it does not follow that the whole has that property. But it is a simple point of logic that a proposition's not following from another is consistent with the proposition's being true.
And so while one cannot straightaway infer the contingency of the universe from the contingency of its parts, it is nevertheless true that the universe is contingent. Or so I shall argue.
The folowing tripartition is mutually exclusive and mutually exhaustive: necessary, impossible, contingent. A necessary (impossible, contingent) being is one that exists in all (none, some but not all) possible worlds. I will assume an understanding of possible worlds talk. See my Modal Matters category for details.
Our question is whether the universe U, all of whose members are contingent, is itself contingent. I say it is, and argue as follows.
1. Necessarily, if U has no members, then U does not exist. (This is because U is just the totality of its members: it is not something in addition to them. If U has three members, a, b, and c, then U is just those three members taken collectively: it is not a fourth thing distinct from each of the members. U depends for its existence on the existence of its members.)
2. There is a possible world w in which there are no concrete contingent beings. (One can support this premise with a subtraction argument. If a world having n members is possible, then surely a world having n-1 members is possible. For example, take the actual world, which is one of the possible worlds, and substract me from it. Surely the result, though sadly impoverished, is a possible world. Subtract London Ed from the result. That too is a possible world. Iterate the subtraction procedure until you arrive at a world with n minus n ( = 0) concrete contingent members. One could also support the premise with a conceivability argument. It is surely conceivable that there be no concrete contingent beings. This does not entail, but is arguably evidence for, the proposition that it is possible that there be no concrete contingent beings.)
Therefore
3. W is a world in which U has no members. (This follows from (2) given that U is the totality of concrete contingent beings.)
Therefore
4. W is a world in which U does not exist. (From (1) and (3))
Therefore
5. U is a contingent being. (This follows from (4) and the definition of 'contingent being.')
Therefore
6. The totality of contingent beings is itself contingent, hence not necessary.
What is the relevance of this to cosmological arguments? If the universe is necessary, then one cannot sensibly ask why it exists. What must exist has the ground of its existence in itself. So, by showing that the universe is not necessary, one removes an obstacle to cosmological argumentation.
Now since my metaphilosophy holds that nothing of real importance can be strictly proven in philosophy, the above argument – which deals with a matter of real importance — does not strictly prove its conclusion. But it renders the conclusion rationally acceptable, which is all that we can hope for, and is enough.
Leave a Reply