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#679 Dialogue with Alex Malpass

April 26, 2020
Q

Hi Dr. Craig,

I really enjoyed hearing you talk with Dr. Malpass about the universe's beginning on Capturing Christianity's youtube channel. I had not realized how nuanced the subject was and I'm very enthusiastic about getting into more of your work on the topic, as well as people like Pruss, Koons and Loke's. When Malpass brought forward his objection involving the symmetry of past and future events, you mentioned you had a five point response but weren't able to get through all of them in the discussion. Do you mind sharing and explaining these five points?

Vincenzo

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Dr. craig’s response


A

Alex himself messaged me after our dialogue to ask what my five responses were to “the symmetry objection,” as I call it, against the argument for the finitude of the series of past events. You’re right that the constellation of questions that arise in connection with this argument are fascinating and of interest to non-theists and theists alike!

By way of review, the symmetry objection asserts that if the argument against the infinitude of the series of past events is sound, then so is a similar argument against the infinitude of the series of future events.

The ironic thing about this objection is that I fully agree that the series of future events cannot be actually infinite, any more than the series of past events can be actually infinite! So in that sense I agree with the symmetry claim. But I claim that it doesn’t follow from the finitude of the series of future events that the series of future events must come to an end.

The series of future events can be finite but endless. In such a case the series is potentially infinite. This is a view that is so widespread and commonly accepted in the history of philosophy and science that the objector has a considerable burden of proof to bear if he is to show that this view is untenable. Can he bear that burden?  I don’t think so, for five reasons.

1. The objection is either ad hominem or question-begging. As Alex recognized, the objection tends to be ad hominem, not in the abusive sense, but in the sense that it has force only against particular people, e.g., those who believe in personal immortality or, in the case of Andrew Loke’s formulation of the argument (see (4) below), against theists. If one tries to avoid this ad hominem feature by claiming that it’s clear that the series of future events can be infinite, then one seems to beg the question. For the objection does nothing to expose a flaw in the reasoning in support of a beginning of the series of past events. It allows that there is a sound argument against the infinitude of the past that also applies to the infinitude of the future. Without refuting this argument, it just assumes that an infinite future is possible, which begs the question against the argument.  So the objection is both question-begging and/or ad hominem.

2. It is plausible that the past and future series of events are not perfectly symmetrical. On a tensed theory of time, according to which temporal becoming is an objective feature of reality, there are no events later than the present event and, hence, no future events. So a tensed theory of time entails that an actually infinite number of future events does not exist; indeed, the number of future events is 0.  The series of events later than any event in time, including the initial cosmological singularity, is always finite and always increasing toward infinity as a limit. In other words, such a series is potentially infinite. Georg Cantor called the potential infinite “a variable finite.” If the series of future events is potentially infinite, then the series of future events is finite but endless.

By contrast the series of events earlier than any event in time cannot be potentially infinite, for in order to be so, it would have to be finite and yet increasing in the earlier than direction, which contradicts the nature of temporal becoming.  So a beginningless series of such events must be actually infinite.

Consider Alex’s premise:

1. If a beginningless series of past events is impossible, then an endless series of future events is impossible.

That commits Alex to the view that there is no possible world in which the series of events has a beginning but no end. In other words, he has to say that the view that the series of events is potentially infinite is not just false but impossible. That is a radical thesis carrying a heavy burden of proof.

3. Landon Hedrick, himself no friend of the kalām cosmological argument, has offered a version of the argument for the finitude of the past that is not susceptible to the symmetry objection. It goes as follows:

(1) There cannot be a world in which an actually infinite number of things have been actualized.

(2) If the actual world is one in which the universe is past-eternal, then there is a world in which an actually infinite number of things have been actualized.

(3) Therefore, the actual world cannot be one in which the universe is past-eternal.

This version of the argument for the finitude of the past avoids any alleged parallelism with the future.

4. Andrew Loke’s version of the argument for the finitude of the past is not susceptible to the symmetry objection. Loke shows that if one holds to the possibility of an infinite temporal regress of events, then it is easy to prove that a simultaneously existing, actually infinite number of things can exist. Loke imagines that the infinite regress of events comprises events involving the construction of hotel rooms from eternity past. By the present time we shall have a hotel with an actually infinite number of rooms. By contrast, if the construction of such a hotel were to commence at the present time, then it would never have an actually infinite number of rooms, though the construction go on endlessly toward infinity as a limit.  Hence, an endless future does not generate the same absurdities as does an infinite past.

Alex’s response to Loke involves an illicit modal operator shift. Alex thinks that if God can bring about the existence of every future room in an endless series of events, then He can bring about the existence of all of them in the present moment. This is a mistake. It does not follow from God’s ability to bring about the present existence of any particular future room that He is able to bring about the present existence of all the future rooms. So to reason is modally logically fallacious. Thus, Loke is quite justified in denying that the possibility of an endless future implies the possibility of the existence of an actually infinite number of things, as does the possibility of a beginningless past.

5. Alexander Pruss’ version of the argument for the finitude of the past is not susceptible to the symmetry objection. Pruss’ argument for the finitude of the series of past events is based on the impossibility of any event’s being the effect of an infinite number of causes. He shows that an event’s having infinitely many causes is riddled with paradox. This rules out an infinite causal regress of events but not an endless causal progress of events, since in the latter no event is the effect of infinitely many causes.

Most of my responses are unfolded in my article “The Kalām Cosmological Argument,” in Two Dozen (or so) Arguments for God’s Existence, ed. T. Dougherty and J. Walls (Oxford: Oxford University Press, 2018), pp. 389–405. May others join in the conversation!

- William Lane Craig