Parodies of Ontological Arguments
(1) By definition, God is a non-existent being who has every (other) perfection.
Hence God does not exist.
(2) I conceive of a being than which no greater can be conceived except that it only ever creates N universes.
I f such a being does not exist, then we can conceive of a greater being -- namely, one exactly like it which does exist.
But I cannot conceive of a being which is greater in this way.
Hence, a being than which no greater can be conceived except that it only ever creates N universes exists.
(3) It is possible that it is necessary that God does not exist.
Hence God does not exist.

The Cosmological Arguments
Plato (c.428 BCE-c.348 BCE), in The Laws, argues that every moving thing must be moved by some cause, and that therefore there must be some self-moving principle that started motion in the beginning.
How can a thing which is moved by another ever be the beginning of change?
Because soul is prior to body, and..body is second and comes afterwards, and is born to obey the soul, then it follows that soul must be the motion which can move itself.
Soul moves our bodies and minds, so therefore soul too must move the heavens.
Thomas Aquinas (c.1224-1274) produced perhaps the classic formulation of the arguments from his Summa Theologica.
Aquinas' "Five Ways":
1.Motion, or the Argument from Change. [Derived from Aristotle] . Whatever is moved must be moved by another, which was itself moved. If we go back in this chain we must come to a "First Mover", which is not itself moved by another, and this everyone understands to be God
2.Causation, or the Argument from Efficient Causality. [Again following Aristotle] This follows a similar line of argument, but replaces motion with cause. Something cannot cause itself for this would mean that it would have to precede itself and that would be impossible. There cannot be an infinite regress of causation otherwise there would be nothing to start off the causal process in the first place.
Aquinas concludes: Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God. This argument is generally known as the First Cause Argument, and is the most popular and of the cosmological arguments.
3.Being, or The Argument from the Ground of Necessity. The world consists of contingent items. That is, items that do not have to exist, or which could have existed differently. There must therefore have been a time when they did not exist, there must have been a time when nothing existed. Since that which does not exist can only be brought into existence by something that already exists, there must be an ultimate source of all being.
We cannot but admit the existence of some being having of itself its own necessity, and not receiving it from another, but rather causing in others their necessity. This all men speak of as God. (Quod omnes dicunt deum).
4.Degrees of Perfection, or the Argument from the Degrees of Being. [A hint in Aristotle, developed by Augustine and Anselm] There are degrees of perfection in the world that enable one to make comparative judgements, such as "this is better (or more beautiful, etc) than that". Assuming that such judgements have an objective foundation, the degrees of perfection necessarily imply the existence of a best, a most true, etc.
What is supreme in goodness (for example) must be the cause of goodness in all things.
Furthermore,since qualities of goodness, truth, being, etc are convertible, there must be a supreme Being which is the cause of being, goodness, truth, and so on, in every other being. And this we call God.
5.The Teleological Argument, or the "Argument from Final Causes"

Leibniz (1646-1716), in his book Theodicy (1710), added to the debate with an additional cosmological argument, that of "Sufficient Reason".
He avoided the problem of an infinite regression by reinterpreting the endless series not of events but of explanations.
He uses the example of a book:
Suppose the book of the Elements of Geometry [A classic by the Greek geometer Euclid] to have been eternal, each copy having been written down from an earlier one.
It is evident that even though a reason can be given for the present book out of a past one, we should never come to a full reason.
What is true of the books is also true of the states of the world.
If you suppose the world eternal, you will suppose nothing but a succession of states and will not find in any of them a sufficient reason.
Even if, he argued, the universe had always existed, there is nothing in it to show why it exists.
According to Leibnitz everything has a sufficient reason.
Therefore the universe as a whole must have one, and it must be outside the universe.
This sufficient reason is what we call God.
It is not the possibility of an infinite series as such which St Thomas denies, but the possibility of an infinite series in the ontological order of dependence.

Kalam's Cosmological Argument as that is the line of reasoning that most theists use to argue for the existence of a god.
1. Everything of type X has a cause.
2. There is something of type X.
3. For some reason (namely, Y), the series of causes of an X must terminate in a first cause.
4. This first cause can be identified with God.
More succinctly: Whatever exists, has a cause; the universe exists therefore the universe has a cause. Are there no problems with these lines of reasoning?

Design (Paley's Teleological Argument)
Is the universe a pocket watch? Can the happenings in the universe be compared to the workings of a pocket watch?
It has been posited that there can be such a comparison.
This is known as Paley's Teleological Argument.
William Paley was a Brittish theologian-philosopher during the 18th century. During his life, he was both a professor of philosophy at Cambridge and a minister in the Anglican Church.
Up until the 20th century, it was a requirement to read his Evidences of Christianity, and his Moral Philosophy in order to earn one's Bachelor of Arts degree.
To this day, his most famous contribution to the study of god is his argument
1. In all things we have experienced that exhibit design, we have experienced a designer of that artifact.
2. The universe exhibits order and design.
3. Given #1, the universe must have a designer. 4
. The designer of the universe is God. Paley's Teleological Argument, put into a broader form, goes like this: Suppose that you were walking along the beach and you came across a pocket watch. If you were to open the watch you would see the guts of the watch - the coils, the springs, the gears, etc. Seeing the results, you would assume that such a thing so wonderful as the pocket watch had to have come to be as the result of a design and someone building it to that design.
Likewise, if we look at the human eye we can see the marvelous complexity of the inner workings of the human eye.
Since you had previously assumed a designer for the wonderful watch, you must likewise assume a designer for the more marvelous human eye.
Going this far, we must take the argument to its natural conclusion that the world and even the universe that we live in must have a grand designer, indeed.