The deceptive first premise of Kalam

To recapitulate the Kalam cosmological argument, it goes like this:

1. Whatever begins to exist has a cause.
2. The Universe began to exist.
3. Therefore the Universe has a cause.

One of the major problems with the first premise is that it's deceptively ambiguous. Especially William Lane Craig is infamous for using this ambiguousness to resort to equivocation fallacies in order to defend the first premise.

The first premise is ambiguous because it doesn't specify what kind of "begins to exist" it's talking about. It implies, but doesn't unambiguously state, that it's talking about creation ex nihilo (in other words, out-of-nothing, ie. first there's nothing, then something appears.)

Assuming creation ex nihilo is unfounded because we have exactly zero examples of this. We cannot corroborate that it happens, and even if it happens, if it has a cause, and even if it has a cause, what that cause might be. Simply assuming that it happens and, especially, that it must have a cause, is completely faulty logic. "It makes sense" is not a valid argument for this.

However, when people like Craig try to defend it, they will switch to the other meaning of "begins to exist", which is the more abstract version, ie. energy/matter transforming from one form to another (in other words, for example a table "begins to exist" when the carpenter builds it.)

This is not a distortion or misinterpretation of what, for example, Craig does. This is exactly his argument. In a video, when responding to the objections to the first premise, he directly states things like "didn't dinosaurs begin to exist? Didn't I began to exist?" and then proceeds to belittle the people who present the objection.

Determining the cause for events

When faced with claims of extraordinary events (such as psychic phenomena or miracles), there are, roughly speaking, two steps to be performed to determine their veracity:

1. Corroborating that the event actually happens.
2. Determining the cause for that event.

These are two very important steps. Jumping directly to the second step is rather moot if the first step has not been corroborated. After all, if the event isn't actually happening at all, trying to discover its cause is a wild goose chase.

The second step is also extremely important, and it's the step that most of these people want to skip. They will spend enormous amounts of time and effort to convince themselves and other people that the extraordinary event is indeed happening... and then just jump to their preferred conclusion, without even attempting to corroborate if that's the true cause.

For example, many believers will spend lots of time trying to convince people that miracle healings do indeed happen. They then just jump to God.

This is, of course, flawed reasoning. Even if the event were really happening, that still doesn't tell us what causes it. That would have to be determined before we can draw any conclusions.

(Of course it doesn't help much that all such extraordinary claims fail miserably even step 1.)

"Anti-supernaturalism"

Some Christian pseudophilosophers accuse scientists and skeptics for being "naturalists" and "anti-supernaturalists." In other words, they accuse them of having the bias and preconception that only the physical exists, and every single phenomenon must have a physical, natural explanation, and that supernatural explanations are rejected outright, without consideration and as a matter of principle.

While extreme naturalists (ie. those who really and honestly think like that, and who willfully reject even the possibility of the existence of the supernatural) are a relative minority of all scientists and skeptics (the majority of them not rejecting the supernatural outright, but considering naturalism as the default position until otherwise demonstrated), even extreme naturalism is quite justified. A lot more justified than the opposite.

The reason for this is that naturalism just outright works, and gives real, tangible results that have a real effect on the real world, and has been so for millenia, while supernaturalism has an abysmal record on this.

Every single step in our technological and medical progress, every single discovery, every single advance in both real-world useful knowledge and in practical applications, has been a pure product of naturalism. In other words, of studying the physical world, finding out how it works, and applying that knowledge to affect our surroundings.

And not only has every single such step been thanks to naturalism, it has been extremely efficient at it. We make more progress via naturalist techniques and approaches in one year than supernaturalism has done in thousands of years.

Supernaturalism is just useless for anything tangible. Our knowledge has not advanced thanks to it, our technology has not advanced thanks to it, our medicine has not advanced thanks to it... in fact, nothing of real tangible value has advanced thanks to supernaturalism. Supernaturalism has not contributed in any way, shape or form to our current level of progress. The only things that supernaturalism has affected are fuzzy abstract notions, opinions, behaviors, feelings and personal subjective experiences. None of which has actually helped progress, nor can be demonstrated to be actually caused by anything supernatural.

So why exactly should one believe in the supernatural? Not only is pure naturalism a good and pragmatic choice, it's the only rational choice.

The "God vs. science" false dichotomy

There seems to be a rather curious deeply-ingrained notion among many of the most fundamentalist Christians and creationists that whatever science cannot explain, God is somehow automatically a valid default answer.

Many of them will spend countless hours trying to discredit science and find holes in it, belittling it, denigrating it and mocking it. Once they find a hole that science cannot currently explain, or the explanation is too esoteric for the average layman to understand, they will cling to it like rabid dogs.

Somehow they have this notion that they can fill these gaps with God. In fact, they often talk like God would be somehow automatically the default valid, and only, alternative. Therefore, if you succeed in "disproving" some aspect of science, you have (they think) automatically proven the existence of God.

This is just an outright false dichotomy. Even if there is something that science can't explain, even if it's something that science will never be able to explain (for example because of our limited resources and the fact that we are bound by physical laws), that doesn't somehow automatically give credence to the existence of a god. It simply means that we don't know, and that's it.

And this isn't even going into the fact that even if we entertained the god hypothesis, we would still know absolutely nothing about this god. These Christians always jump from "the god explanation" to "the God of Christianity", as if that would be a completely sensible and valid thing to do.

This can be really blatant sometimes. I was once engaged in an online conversation with a Christian, and the subject was precisely this. When I asked how can we know anything about this hypothetical god, he literally started quoting the Bible, as if that were the completely natural and logical thing to do.