(1) Anything that begins to exist requires a cause
(2) The universe began to exist
(3) Thus, the universe requires a cause
Additional reasoning leads us to conclude that the cause of the universe is God. Given that whatever caused space, time, and matter to begin to exist cannot itself be spatial, temporal, or material. Furthermore, whatever caused our orderly universe to come into being a finite time ago must be immensely powerful, intelligent, conscious, and hence personal. These are apt descriptions of a being theists have long identified as God.
Some seek to undermine this causal argument for God’s existence by denying the first premise. They point to quantum mechanics and virtual particles as evidence that there are exceptions to the causal principle.
In regards to quantum mechanics, an appeal is made to Heisenberg’s Indeterminacy Principle. This principle holds that one cannot accurately determine with precision both the position and momentum of an electron at the same time. If you measure its momentum, its position changes. If you measure its position, its momentum changes. Thus, it is impossible to accurately predict the future motion of an electron. While this is a physically accurate description of what we observe on the quantum level, some have improperly understood this to mean that the momentum of electrons is uncaused. This is an unjustified use of science. Heisenberg’s principle pertains to predictability (of the location and momentum of subatomic particles), not causality. “The mere fact that we can’t predict something doesn’t mean that something has no cause.”
What about virtual particles? The quantum vacuum is a sea of fluctuating energy. Heisenberg’s Indeterminacy Principle allows for pairs of virtual particles to come into existence for a fleeting moment before being subsumed back into the vacuum. Detractors of the kalam argument point to these virtual particles as examples of entities that come into being without a cause. But this conclusion is unjustified given the evidence. While we may not be able to observe the cause, that does not mean there is no cause. Given our uniform experience of cause and effect, it is more likely to conclude that a cause exists that we have yet to detect than it is to conclude there is no cause. Indeed, the best explanation may be that virtual particles are caused by the quantum vacuum from which they originate.
For some, such explanations will not be sufficient. Until a cause for particle pair production can be observed or detected, they will maintain that it is more reasonable to conclude that such events are uncaused. This brings me to what I consider the ultimate rebuttal to scientific challenges to the first premise: science cannot, in principle, ever identify an uncaused effect, and thus it is never reasonable to conclude on the basis of science that something exists for which there is no cause. Let me explain.
Science contributes to our knowledge of reality by making observations about physical things. If they are able to directly or indirectly observe some X, then we have good grounds for adding X to our ontology. For example, when scientists detect a new particle such as the neutrino, we add neutrinos to our list of things that exist. While science can identify what exists by what it observes, science cannot identify what does not exist by what it fails to observe. If science cannot identify what does not exist by what it fails to observe, then the failure to observe a cause for particle pair production does not entail the absence of a cause.
Imagine for a moment that a scientist is barbequing some steaks in his backyard. While he is cooking, a piece of chicken suddenly appears on the grill. Strangely enough, it only appears for a brief moment before disappearing again. This happens multiple times. Quickly, the scientist grabs his instruments in hopes of detecting what is causing the chicken to appear on his grill. Despite all attempts to detect the cause, however, he finds nothing. Does this mean there is no cause? No, it just means he has failed to detect the presence of a cause. Perhaps the cause is too small or operates too quickly to be detected by his instruments. While he cannot rule out the possibility that the chicken’s appearance was uncaused, as a scientist he knows his failure to detect a cause is not proof that there is no cause. Absence of evidence for a causal entity is not evidence for the absence of a causal entity.
While the scientist can rightly claim he does not observe a cause for the chicken’s appearance on his grill, he cannot claim science has proven there is no cause. Likewise, while scientists do not detect a cause for the appearance of virtual particles in the vacuum, the absence of evidence for a cause is not itself evidence for the absence of a cause. It is beyond the scope of the scientific method to make conclusions about what does not exist. If there is such a thing as an uncaused entity, it would be impossible to identify it scientifically because science is based on observation and induction. It is impossible to observe the absence of something, and thus it is impossible to discover an uncaused entity by scientific methods. If uncaused entities exist, they must be identified philosophically, not empirically/scientifically.
Norman Geisler and Frank Turek, I Don’t Have Enough Faith to Be an Atheist (Wheaton, IL: Crossway Books, 2004), 87.