Arguments for the existence of God

Can anyone help me with some information regarding ‘proof’ of God’s existence?
I am discussing the mathematical probability of creation being random vs. intelligent design. I recall reading that the probability for random creation is so high as to make it’s liklihood prohibitive. Can anyone direct me to some internet sources giving the figures and discussion? Anyone have any interesting facts and figures in this regard?

I am also interested in information reading the ontological argument used by St. Anselm. I understand that this was addressed by St. Thomas Aquinas who debunked the argument so effectively that it was dropped as a tactic for some considerable time. Does anyone have enough familiarity with the works of St. Thomas to know what Aquinas said about it and what he used instead? What in summary was the ontological arguments’ strengths and weaknesses? How does St. Anselms version differ from Descartes?

Finally, does anyone know any other good arguments that have been used?

I’m in a bit of a rush at the moment, so I can’t go into to detail over your questions (although I may come back later). I would suggest going to He has some excelent arguments listed.

I do not know who you are debating on this topic, but here is something that might help. Most people who disagree with intelligent design do not beleive in random chance either.

The universe is not a random place. There are laws and forces that cause matter and energy to act in specific ways. Chemicals have tendencies to bond in specific ways with other chemicals etc. etc. So usually you would not be arguing with someone who actually believes that the universe got the way it did by a series of cosmic rolls of the dice (but you might be).

It would be good to know which type of person you are debating first. It is not a debate which has only two possibilities, either intelligent design or complete random chance.


The difference between Anselm’s method and Aquinas’ method is direction of inference.

Anselm argued deductively, a priori, which means he argued from first principles to consequences.

If A Then B.
A is true, therefore B is true.

“That above which none better can be conceived must have the property of existence. God is that above which none better can be conceived, therefore it must be true that God exists.”

Aquinas argued a posteriori.

Thing A causes Thing B
B exists, therefore A exists.

“Created things exist, therefore what created them exists.”

The a posteriori form of argument is rampant in the Psalms and the Wisdom literature of the Old Testament. When you look at the radiant form of Creation, you affirm that it must have an ultimate cause.

Anselm’s method is a classical deductive argument, taking its ground strictly from concepts and their necessary relations, while Aquinas takes his ground from the data of senses.

Anselm’s argument is more respected by many modernists, but most poke a hole in it by noting predicating existence of a thing adds no information to it; “existence” is not a meaningful property like “red” or “round.” As Wittgenstein might say, that something exists is something that can be shown but not said. A scientist who says that DNA is protein doesn’t separately assert that DNA exists. That it exists is “metaphysical” because saying it exists doesn’t add anything to what is implied by its other predicates.

Some practical advice for you: famous atheist Anthony Flew of Cambridge (?) recently and very publicly abandoned his atheism not by analytical mathematical arguments, but by the appeal of nature’s complexity, which is the Thomistic route. Ultimately, if someone isn’t impressed by the radiant form of creation, they’re not going to get anywhere until they let go of the fairy tale of self-sufficiency.

I haven’t quite worked this out completely in my head, but one thing I’ve been thinking about lately is something I saw at work the other day. One of my co-workers had a clip-board that had “I AM SELF MADE” written in marker on the back of it. I don’t know why, or what the person who wrote that meant, but my first thought when I saw that clip-board was, “That’s ridiculous; nothing is self-made.” Having never considered the fact in a concise statement, I had to stop and think about what the consequences of that statement are. They’re sort of startling, when you follow that train of thought through (whether the conclusion which you come to is theism or atheism).

Sorry no further resources; I just felt like putting my two cents in.

As I understand it, Descartes also characterizes the ontological argument as a proof from the “essence” or “nature” of God, arguing that necessary existence cannot be separated from the essence of a supremely perfect being without contradiction.

Can anyone offer any further explanation of this?

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