The Kalam Cosmological Argument

The Kalam Cosmological Argument (KCA) is a cosmological argument that has its roots in Islamic theology. It has been popularized in the West by Christian philosophers such as William Lane Craig.

Formulation

1. Everything that begins to exist has a cause.
2. The universe began to exist.
3. Therefore, the universe has a cause. (1, 2)

The above is typically referred to as the "first stage" of the KCA. Typically, the arugment follows to argue that this cause must be immaterial, timeless, spaceless, and personal, known as the "second stage".

Causality and the First Premise

The first premise is a causal principle that seems to be intuitively true. It's intuitively true because it's intuitive, it's supported by inductive reasoning, it's supported by empirical evidence, and it's proved helpful in scientific inquiry. Furthermore, it allows the proponent to easily dismiss the common objection, "what caused God?" by simply asserting that God did not begin to exist.

For an object to begin to exist at time , that means that it exists after time but not before time - that is, the object has an earliest temporal boundary at time . But with that definition, where have you seen something begin to exist, at all? When, for example, a car is built, the car itself does not begin to exist. The car is just a rearrangement of pre-existing matter, where pre-existing means that it is ontologically and temporally prior.

In fact, we can construct a mirror argument to the KCA:

1. Everything that begins to exist is made of pre-existing (ontologically or temporally prior) stuff.
2. The universe began to exist.
3. Therefore, the universe is made of pre-existing stuff. (1, 2)

This mirror argument would then challenge the creation of the universe ex nihilo, which then disproves traditional theism. Additionally, the mirror-premise has the same intuitive support as the original premise; it's intuitive, supported by inductive reasoning, supported by empirical evidence, and proved helpful in scientific inquiry. It even underpins conservation laws, providing a very grounded basis for scientific inquiry.

The Second Premise

The second premise states, simply, that the universe began to exist. There are two ways to approach the analysis of this premise; one is scientific, and the other is philosophical.

Scientific Analysis

There is no scientific consensus on whether the universe began to exist. The Big Bang Theory does not say that the universe began to exist; it says that the universe was in a hot, dense state around 13.8 billion years ago. More specifically, at that time, our local spatiotemporal manifold began expanding from an high-energy, high-density single point. However, the Big Bang Theory does not say anything about the universe's existence before that point. There could be other spatiotemporal manifolds that temporally precede our own.

To support the lack of consensus, Graham Oppy has written the following:

"There is currently no widespread consensus among expert cosmologists about whether we live in something like a standard big bang universe or whether our universe is part of an infinite ensemble of universes in a background de Sitter space in which there is an infinite causal regress."

Additionally, the idea of time itself is a subject of debate. Even if we grant past-finitude (that the universe has a finite past), that does not imply that the universe began to exist. Prior to the beginning of a metric time (like the one we experience), there could have been a pre-metric time; it could be amorphous (like a timeless state), or it could be undifferentiated (like a state where time is not a meaningful concept). The universe could also simply be timeless before metric time, and then temporal after metric time.

A good intuition for this is to think of "What is temporally prior to the Big Bang?" as akin to "What is north of the North Pole?" - the latter is obviously a nonsensical question, and the former might be as well.

Philosophical Analysis

Many philosophical justifications for the second premise rely on the impossibility of an actual infinite; that is, a collection of things that has no beginning and no end. More formally, an actual infinite is a collection of things that can form a one-to-one correspondence (a bijection) with the set of natural numbers .

First, the argument from successive addition states that you can't form an actual infinite by adding one thing at a time. But for an infinite past, one is not beginning with a starting finite set and adding to it; one is beginning with an infinite set and adding more to it, resulting in, still, an infinite set.

One response is that if you cannot count to infinity, then you cannot count down from infinity either. However, there is a difference between counting to infinity and counting down from infinity; the reason that it is impossible to count to infinity is that the set of natural numbers does not end; there is no predecessor to . However, the past does have an end - the present.

Second, there is a common argument that actual infinites cannot exist based on Hilbert's Hotel. This argument states that if you have a hotel with an infinite number of rooms, and all the rooms are full, you can still accommodate a new guest by moving the guest in room to room . Similarly, if you have an infinite number of guests, you can accommodate a new guest by moving the guest in room to room . This argument is meant to show that actual infinites lead to absurdities. However, this argument is not convincing. Here are some reasons why:

1. These "absurdities" are a result from manipulating numbers (the room numbers), but obviously, you can't manipulate past events in the same way.
2. Even if we grant that these absurdities are real, one could dismiss them as a result of mathematical realism - the belief that mathematical objects exist independently of human thought - because we can cacept that there are infinitely many mathematical objects. (This is opposed to nominalism, which states that mathematical objects are just useful fictions.)
3. Taking a step further, let's grant the entire argument; that actual infinites lead to absurdities. But that also means that the future cannot be infinite. The future is an actual infinite - it is a collection of what will happen (not what would have happened at some point in the future.) - and so, the future cannot be infinite. Think of it as the answer to "how many days from now on will occur?". Each following day can be paired with a natural number, and hence form a bijection with , becoming an actual infinite. Additionally, according to eternalism, the future is just as real as the past - it already exists in the same way that the past does - further supporting the idea that the future is an actual infinite. This contradicts against traditional theism, which states that the future is infinite (the afterlife, eternal life, etc.).

Third, there are some arguments for causal finitism, which states that there cannot be an infinite causal chain. A Benardete paradox goes as follows: suppose that there is an infinite chain of dominoes, each knocking down the next. If the chain is infinite, then there is no first domino to start the chain. But if there is no first domino, then the chain cannot start. This argument is meant to show that an infinite causal chain is impossible. However, this argument is not convincing either because Benardete paradoxes rely on a logically inconsistent logical structure (unfortunately, the paradox is too long to explain here), and even if granted, it could also be applied to the future.

In conclusion, the second premise is not as well-supported as it seems, and there are many objections to it.

The Conclusion

The conclusion of the KCA is that the universe has a cause. However, the KCA does not lead to a theistic conception of God.

First, one could argue that because the cause is immaterial, and it has causal power, it must be a mind. There are other possible explanations for an immaterial cause with causal power, such as a timeless quantum field, a universal wavefunction that is not spatially or temporally bound, the Tau (a hypothetical particle that is the cause of the Big Bang), or other naturalistic explanations. Additionally, all minds that we know of are bound/embodied in spacetime, yet the cause is not bound in spacetime. This is a contradiction. Also, the assertion that the cause is immaterial is not well-supported because it could be material but timeless (non-metric time, amorphous time, etc.).

Second, another argument is that since a timeless cause is creating a temporal effect, this must come from a personal or free agent. However, this is not necessarily true; the only criteria is that the cause is not sufficient to necessitate the effect, meaning that only indeterministic causation is required, and impersonal indeterministic causation is possible (quantum mechanics).

Third, some argue that in order to create the universe, the cause must be very powerful. However, this is not necessarily true; the cause only needs to initiate a causal chain, not sustain it (existential inertia - the idea that temporal concrete objects continue to exist even under the absence of sustaining causes, so long as they are not destroyed by external causes). In order to begin metric time, it simply needs to cause change - that's it. Even an indeterministic quantum fluctuation could achieve this.