Can anyone provide an argument for a necessary being?

[RobbyPants]

If we can all agree that everything in the known universe does indeed have a beginning and an end, then we can rule out the idea that things can go on existing ad infinitum and also that the universe could have existed forever, can we not? If we can, then positing some prime mover or creator being for the origin of the universe does not seem to me to be out of the question. Conversely, and nobody seems to want to tackle this, is the question of what would be a plausible alternative explanation for the origin of the universe without an agent that brings it into existence and sets it all into motion. Please, dear fellow thinkers, bring forth your best fruits and lay them on the table for us all to examine openly.

We can agree that everything we've observed thus far has a beginning. We haven't observed the beginning of the universe, so it's speculation.

Now, you might be entirely right in assuming the universe, too, has a beginning. You also might be making some induction failure and be entirely wrong. If every male you've ever met has a beard, you might assume that all males have beards.