This is the weekly Q & A blog post by our Research Professor in Philosophy, Dr. William Lane Craig.


Dr. Craig,

My name is Tejas and I'm 13 years old. I admire you and have watched many of your debates. I sincerely request you to answer this question, and thank you for taking your time to read this.

My question regards the Kalam Cosmological Argument, that I have seen you present in some debates. The first part is, is the initial premise on causation refuted if the zero-energy universe hypothesis is true, and what would be the flaws if the universe were a vacuum fluctuation? And regarding the second premise, could you please tell me why you think the presentism ontology of time is true?

I thank you so much and apologize if there seems to be any disrespect in the question. Please do answer this question.

Thanks so much,

Warm regards,



Dr. William Lane Craig’s Response

Dr. William Lane Craig

Need I say how impressed I am, Tejas, that someone so young should be interacting with such difficult questions?

Your first question concerns the possibility that the positive energy associated with matter might be exactly counter-balanced by the negative energy associated with gravity, so that on balance the net energy of the universe is zero. In my QoW #389 I deal with this hypothesis insofar as it implies the finitude of the past.

Your question is how such a hypothesis affects the causal premiss of the kalam cosmological argument. I have heard scientists say that if the net energy of the universe is zero, then the universe need not have a cause of its beginning to exist because nothing really exists, so that we do not have the absurdity of something’s coming from nothing.

This attempt to draw metaphysical implications from the zero net energy hypothesis is a bad joke. It’s like saying that if your debts and your assets exactly cancel each other out, so that your net worth is zero, then there is no cause of your current financial condition. The suggestion that nothing exists is absurd. Not only do I undeniably exist, but according to the hypothesis the positive and negative energy exist. So as Christopher Isham, Britain’s premier quantum cosmologist, points out, there still needs to be “ontic seeding” to create the positive and negative energy in the first place.[1]

As for vacuum fluctuation models of the universe, you’ll find these discussed in Reasonable Faith, 3rd ed. (Crossway, 2008), pp. 31-33. The fundamental shortcoming of these models was that the quantum vacuum, if past eternal, would eventually be filled with fluctuation-formed universes, which would collide and coalesce, so that we should be observing an infinitely old universe, not a relatively young one.

As for presentism, I hold to it because I think that it is the most coherent tensed theory of time that there is. Presentism holds that the only temporal entities that exist are present ones. Presentism is one version of a tensed theory of time. I endorse a tensed theory of time. That is to say, on the basis of the ineliminability of tense from human thought and discourse and our experience of the present, not to mention the grave problems with tenseless views, I think that there is an objective difference between past, present, and future and that temporal becoming is a real and objective feature of reality. Given a tensed view of time, the question then becomes: which theory of tensed time makes the most sense? I argue in my Time and Eternity (Crossway, 2001) that only presentism avoids the incoherence known as McTaggart’s Paradox and is therefore the superior view.

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