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#658 On the Interview with Sir Roger Penrose

December 01, 2019

Dear Dr. Craig,

I listened to your interaction with Sir Roger Penrose on Unbelievable?, and I was interested in your claim that absolute metaphysical time exists. I have a concern about the coherence of metaphysical time. If metaphysical time exists, then it will always make sense to say that some past event occurred x amount of time ago, even if time becomes impossible to measure physically (e.g. all timekeeping processes disappear). This implies that it is impossible for metaphysical time to cease to exist. If it is impossible for metaphysical time to cease to exist, then how is it possible for metaphysical time to come into existence? The alternative would be that metaphysical time is past eternal, which is a stance you would reject.


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Dr. craig’s response


Ah, our old friends the A- and B-Theories of time make themselves felt once again! By way of review, an A-Theory of time is a theory of tensed time: things really are past, present, or future, and temporal becoming is real. The B-Theory is a theory of tenseless time: all moments in time are equally real, and there is no objective past, present, or future, just the subjective standpoints of observers along the line of time.

I am a partisan of an A-Theory and so approach the question at hand from that standpoint. I think that God’s time, metaphysical time, exists independently of any physical measures we might try to make of it. The possibility of God’s experiencing a sequence of mental events prior to creation is, in my opinion, a knock-down argument that time is not identical to any physical time.

So I wholeheartedly agree that time itself would not cease to exist even if all time-keeping physical processes ceased to exist, as Penrose imagines. Penrose seemed to embrace a verificationist, reductionistic view of time that is oddly out of step with his metaphysical predilections.

I also agree that it is impossible that metaphysical time cease to exist. Even if God were to annihilate the universe, it would still forever after be true that “A universe used to exist” and there would be indefinitely many past-tense truths, which is sufficient for time’s existence.

But on an A-Theory of time, the past and future are not symmetrical. There is an arrow of time determined by the direction of temporal becoming from past to future. Thus, although time, having come to exist, cannot cease to exist, there is no reason that time cannot have a beginning at which it first exists. God existing changelessly alone without creation, may thus be conceived to exist timelessly sans creation, and time begins at the moment of creation.  

- William Lane Craig