Nor can the Uncaused Cause of theism be identical with the material universe, as many atheists believe. As ordinarily conceived, the cosmos or material universe is a limited and spatio-temporal system. It is, for example, subject to the Second Law of Thermodynamics and thus is running down. But an Uncaused Cause is unlimited and not running down.

Space and time imply limitations to a here-and-now kind of existence. But an Uncaused Cause is not limited, and so it cannot be identical to the space-time world. The theistic God is in the temporal world as its ground of continuing existence, but He is not of the world in that it is limited and He is not.

If, in response, one claimed that the whole of the material universe is not temporal and limited as are the parts, he would only demonstrate what theism claims, for his conclusion is that there exists beyond the contingent world of limited spatio-temporality a whole reality that is eternal, unlimited, and necessary. In other words, it agrees with theism that there is a God beyond the limited, changing world of experience. It is a substitute for God that admits that there is a whole reality that is more than the experienced part of reality and that has all the essential metaphysical attributes of the theistic God.