The cosmological argument really needs to die already.

[Simon Moon]

The modus ponens form of this argument is invalid.

The argument, in any version, is guilty of the fallacy of equivocation, among others.

In premise 1. the phrase 'begins to exist' is referring to creation ex materia. In other words, the rearrangement of already existing matter and energy.

Then, in premise 2, 'began to exist' is referring to creation ex nihilo.

Same phrase, 2 meanings = Fallacy.

If you rephrase the argument using the 2 meanings, you get -

1. Everything that is a rearrangement of existing matter/energy has a cause.
2. The universe is a rearrangement of existing matter/energy.
3. Therefore the universe has a cause.

As you can see, premise 2 in this argument does not say what theists want it to say.

If we use the other meaning -

1. Everything that is created out of nothing has a cause.
2. The universe was created out of nothing.
3. The universe has a cause.

Now we see that premise 1 is suspect because we have no examples of things that were created out of nothing to examine.

There is also the fallacy of composition. Just because something is true of a part of the whole, does not mean it is true of the whole.

It is a very weak argument that seems to be convincing to theists.

EDIT: I found another rephrasing of the argument that also shows the equivocation fallacy, on Ironchariots.com -

1. Every rearrangement of pre-existing matter has a cause. (supported by every observation, ever.)

2. The universe began to exist from absolute nonexistence, NOT from a rearrangement of pre-existing matter.

3. Therefore the universe has a cause.

In other words:

1. Every X has a cause.

2. The universe Y.

3. Therefore the universe has a cause.