Given your present beliefs, it logically follows that a necessarily existent Being capable of spontaneous free action exists.

You believe that it is possible for a maximal collection of contingent things, C, to exist. Now C would be a contingent thing, since C’s non-existence is possible (this follows from the fact that every part of C is contingent, and C only exists if all its parts exist).

You also believe that any contingent thing (other than a free action) that begins to exist must have a cause. That means that if C began to exist, it must have a cause. No contingent thing could possibly cause C or any other maximal collection, since every contingent thing compatible with C is part of C, given that C is maximal (and no cause can be part of its effect, as I stipulated at the outset). Therefore, the only possible cause of C has to be a non-contingent being, a.k.a., a necessarily existing Being—a being that, by definition, exists in every possible world, if it exists at all.

Now if any possible world had a being that exists in all possible worlds, then that being would exist in the actual world, too (given the modal axiom, S5). It follows that if it is really possible for C to have a cause, then there really is a necessarily existent Being, N.

Now N can cause C by a free action, by a non-free action, or by a non-free non-action. In all three cases, N’s causing C would be a contingent state of affairs, for otherwise C would be necessary, which is a contradiction. Since C contains every contingent thing compatible with it other than free actions, C also includes N’s causing C, unless N’s causing C is a free action. But if C includes N’s causing C, then N could not cause C without causing N’s causing C, which is circular. Therefore, N’s causing C cannot be included in C, which entails that N’s causing C is a free action.

Note: I did not assume at the outset that some free actions are impossible to cause. Rather, I left it open whether or not free actions would be an exception to the general principle that every beginning has a cause. One can believe that every beginning other than free actions possibly has a cause without being sure if any free actions would require cause. However, once one follows the above argument, then one may see that some free actions don’t require a cause.

Your beliefs may have further implications. Would you like to Continue?