1) Anything that begins to exist must have a cause adequate to explain it.
2) The universe began to exist.
3) Therefore, the universe must have a cause adequate to explain it.
The first "premise" of the argument seems to be obviously true. Cakes don't bake themselves. Houses don't build themselves. Paintings don't paint themselves. If you hear a knock at your front door, you don't assume that it knocked itself. Each of these things requires a "cause" -- Cakes require bakers; houses require builders; paintings require artists. None of this is controversial.
So, don't worry about the second line of the argument yet. Just consider this: If we have evidence that our universe came into existence at some point in the past, it is perfectly reasonable to conclude that there must be a "cause" for that too. Not only must there be a cause, but when the "effect" is the entire universe -- everything physical thing we know to exist or have ever existed -- the "cause" of that must be immensely powerful.
It must be something like what we call, "God."
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