- Everything that exists has a cause of its existence.
- The universe exists.
Therefore: - The universe has a cause of its existence.
- If the universe has a cause of its existence, then that cause is God.
Therefore: - God exists.
Kalam cosmological argument
- Whatever begins to exist has a cause.
- The universe began to exist.
- Therefore, the universe has a cause.
Argument based on the impossibility of an actual infinite:
- An actual infinite cannot exist.
- An infinite temporal regress of events is an actual infinite.
- Therefore, an infinite temporal regress of events cannot exist.
Then we have...
Thomistic cosmological argument
- What we observe in this universe is contingent (i.e. dependent, or conditional)
- A sequence of causally related contingent things cannot be infinite
- The sequence of causally dependent contingent things must be finite
Leibnizian cosmological argument
- Every existing thing has an explanation of its existence, either in the necessity of its own nature or in an external cause.
- If the universe has an explanation of its existence, that explanation is God
- The universe is an existing thing.
- Therefore the explanation of the universe is God.
- Every finite and contingent being has a cause.
- A causal loop cannot exist.
- A causal chain cannot be of infinite length.
- Therefore, a First Cause (or something that is not an effect) must exist.
The arguments also suffer from a fundamental misunderstanding of the universe. The Big Bang Theory, which lends weight to the claim that the universe even had a beginning, involves space and time’s origin as well. Ask a layperson to describe the Big Bang and you’ll likely hear about an explosion in space from which all matter and energy came forth to eventually form stars, planets, etc. I would guess this misconception draws the ignorant to the First Cause arguments. The scientific consensus is that space/time exploded outward with the matter and energy that eventually formed the universe. Scientists determined this, in part, from observations of celestial bodies drifting apart, marking the predicted expansion of space. The repercussions of this accurate understanding of the Big Bang Theory means that time began at the moment of the effect (the Big Bang) leaving no time for the cause. This leaves the apologist with the task of weighing which counter-intuitive statement is more logical--that every effect must be preceded by a cause or that anything can precede the arrow of time. It’s quite the chronological conundrum...that somehow doesn’t bother theists that much.
I’m not sure “logical” is the operable word here. At the first moment of the Big Bang, and therefore time, everything that would become the universe was a singularity, or something close to it. At this size it was subject to the strangeness that is quantum mechanics. While scientists don’t yet have clear explanations for everything we observe at the quantum level, we have repeated and repeatable results that inform particle/wave duality, the uncertainty principle, super positioning and all kinds of other phenomenon that most everyone would say seems impossible if they don't see it with their own eyes and instruments. Some of these phenomenon even open possibilities that may violate causality and the arrow of time. I look forward to having my mind further blown as humanity hashes this all out.