Allow me to present the actual argument, rather than the mutilated straw man offered by one of the previous reviewers.
Principle of causality:
Everything which begins to exist, has a cause for its beginning.
This is a self-evident principle. It is not made up, "conjured," "mystical," or any of the other ad hominem remarks of the prior reviewer.
It is also patently obvious and unquestionably true. If something begins to exist, it either has a cause--a principle of its being--or it does not. If it has no principle of being, no reason for its coming to exist, it has come from nothing and nowhere. But this is impossible; ex nihilo nihil fit. Out of nothing (absolutely nothing, meaning not a blank void, not a vacuum, not empty space, but literally NOTHING) nothing can come. Hence everything which begins to exist has a cause.
Now in the world we see many things which are caused. I press the keyboard, causing words to appear on the screen. You throw a baseball through a window, causing the glass to break. And so forth.
We can also take an example of an ascending series of causes. The brush causes paint to spread over the canvas, the artist's hand causes the brush to move, the artist's arm causes the hand to move, the brain causes the signal to be sent to move the arm, and so forth.
This sort of series--an essentially subordinated series of causes--cannot proceed indefinitely/infinitely. Why not?
Take the following example (with credit due to one of my past philosophy professors).
You go to a movie theater. You approach the ticket window, motion to the man standing behind you, and say "He'll pay for my ticket."
Then the second patron comes to the window, points to the third guy, and says "He'll pay for both of us."
If the third, fourth, fifth, and ten millionth customer do the same, then the poor person who is last in line will have an industrial-sized ticket price.
But if the line is infinitely long, if--literally--the line is without end (because that is what the "infinite" means) then the theater will never get its money.
The theater stands analogously for reality, the patrons of the movie stand for contingent beings which do not exist necessarily (for instance, those now reading this review did not exist 200 years ago; hence they are contingent), and the money stands for existence.
Because all of the movie-goers defer payment to the last person in line, and because there is no last person in line, there is no money, and the theater is never paid. Because all contingent beings, being non-necessary, defer explanation of their existence to another, and because the deferral cannot proceed forever if we are indeed to acknowledge that things really exist, there must a Being Who does not defer the explanation of His existence, because He is His own existence, Ipsum Esse Subsistens.
No special pleading, no question begging, no logical fallacies. All of this is common sense, rendered more philosophically rigorous by classical metaphysics.
On the contrary, atheists like "Beth," so long as they admit that anything at all exists, assert the following, analogously:
1. The last person in the theater line pays the whole ticket price.
2. There is no last person in the theater line.
3. The theater receives its money.
More obvious examples of contradiction are hard to come by.
The review offered by "Beth" is a sad example both of philosophical ignorance and of emotionalism in argumentation.
The relentless petty insults, misrepresented arguments, ad hominems, accusations of non-existent logical fallacies, and gratuitous shots at believers, lead one to believe that the reviewer is actually trying--unsuccessfully--to convince herself of the atheism she latently knows to be logically impossible.
Unfortunately, the review by "Beth" no longer exists, proving its own contingency.