Thursday, April 30, 2009

Thomas Aquinas' Arguments for the Existence of God



Most arguments for the existence of God provide evidence based in probability (a la Pascal) rather than proofs to a mathematical certainty. You can always wiggle-out of them by denying this-or-that.

By way of illustration, a painting may exist, but how does a painting "prove" the existence of a painter in general, or a specific painter in particular -- couldn't the painting have been formed by some as-yet undiscovered natural cause(s)? In the absence of actually presenting the painter who painted it, isn't it best to be skeptical when someone points to a painting, and goes around proclaiming, "painter"?! And, in the case of a 200-year-old painting, the painter, if there ever was one, is now dead, so no proof that there was a painter is now possible.

A lot will depend on how motivated you are to deny the existence of the object in question. In the case of God, many atheists show a high emotional commitment to denying God's existence. For example, in my previous post, one commenter said, "why couldn't something come into existence uncaused?". When the subject in question is the entire universe, the uncaused existence of a mere painting should be a walk in the park. A second commentator threatened me with physical violence. So, when it comes to God, a lot of people on both sides of the issue have a lot invested in it emotionally.

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Thomas Aquinas (born ca. 1225; died 7 March 1274) was a priest of the Roman Catholic Church in the Dominican Order from Italy. He is frequently referred to as Thomas because "Aquinas" refers to his residence rather than his surname.

He was the foremost classical proponent of natural theology, and the father of the Thomistic school of philosophy and theology. His influence on Western thought is considerable, and much of modern philosophy was conceived as a reaction against, or as an agreement with, his ideas, particularly in the areas of ethics, natural law and political theory.
(Wik).

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Here are Aquinas' five classic arguments, offered in concise form. Some are more convincing than others. All reflect a thoughtful philosopher-theologian's attempts to argue from "natural theology" as opposed to revelation.

Aquinas' First Argument, Motion
(1) Objects are in motion.
(2) If something is in motion, then it must be caused to be in motion by something outside of itself.
(3) There can be no infinite chain of movers/movees.
(4) So there is a first, unmoved mover.
(5) This first, unmoved mover is God.
(6) Therefore, God exists.

Aquinas' Second Argument, Causality
(1) Some events cause other events.
(2) If an event happens, then it must be caused by something outside of itself.
(3) There cannot be an infinite chain of cause and effects.
(4) So, there is a first, uncaused cause.
(5) This first, uncaused cause is God.
(6) Therefore God exists.

Aquinas' Third Argument, Contingency
(1) Contingent things exist.
(2) Each contingent thing has a time at which it fails to exist (contingent things are not omnipresent).
(3) So, if everything were contingent, there would be a time at which nothing exists (call this an empty time).
(4) That empty time would have been in the past.
(5) If the world were empty at one time, it would be empty forever after (a conservation principle).
(6) So, if everything were contingent, nothing would exist now.
(7) But clearly, the world is not empty (premise 1).
(8) So there exists a being who is not contingent.
(9) This non-contingent, i.e., "necessary" being is God.
(10) Therefore, God exists.

Aquinas' Fourth Argument, Properties That Come in Degrees
(1) Objects have properties to greater or lesser extents.
(2) If an object has a property to a lesser extent (such as, e.g., "goodness"), then there exists some other object that has the property to the maximum possible degree.
(3) So there is an entity that has all properties to the maximum possible degree.
(4) This entity is God.
(5) Therefore, God exists.

Aquinas' Fifth Argument, From Design
(1) Among objects that act for an end, some have minds, whereas others do not.
(2) An object that acts for an end, but does not itself have a mind, must have been created by a being that has a mind.
(3) So there exists a being with a mind who designed all mindless objects that act for an end.
(4) This being is God.
(4) Therefore, God exists.

8 comments:

Anonymous said...

So many false premises, so little time.

The first one is this:

"If something is in motion, then it must be caused to be in motion by something outside of itself."

Untrue. My dog just ran by and he achieved his motion by moving his legs - no "something outside of himself" caused him to move.

"(1) Some events cause other events.
(2) If an event happens, then it must be caused by something outside of itself."

In number 1 you claim "some events", and then in number 2 you say EVERY event.... moving goal posts.

I don't follow your "contingent thing" rationalizing.

"If an object has a property to a lesser extent (such as, e.g., 'goodness'), then there exists some other object that has the property to the maximum possible degree."

I disagree... there is no "maximum goodness" for instance, as what is "good" is subjective. You think religion is good for instance.

"An object that acts for an end, but does not itself have a mind, must have been created by a being that has a mind."

Why? Why does it have to have been "created" at all??

None of this was AT ALL convincing....

KC said...

I've never really been that interested in proof about the existence or non-existence of god. I'm agnostic but if there is a god thats great!

That fact alone however doesnt for a minute provide any basis whatsoever for any of the religions of the world--which is what I am most interested in. All of the ones I've studied exist on pretty shoddy evidence.

Nor does the existence of a god prove that what that god wants is for us to believe in him.

In other words, proving the existence of a god proves very little.

Anonymous said...

"In other words, proving the existence of a god proves very little."

Very good point.

I have to say - if I woke up tomorrow and found that god had presented himself as proof that he exists, my life wouldn't change one bit. I cannot imagine what I would change about my life with such information - nothing would change for me. I would live how I currently live.....

BallBounces said...

So many false premises, so little time.

The first one is this:

"If something is in motion, then it must be caused to be in motion by something outside of itself."

Untrue. My dog just ran by and he achieved his motion by moving his legs - no "something outside of himself" caused him to move.

* The dog in motion was itself caused by something else, i.e., procreation. The dog does not cause itself.

I don't follow your "contingent thing" rationalizing.

* It's not mine -- it belongs to Aquinas. It is an observation from philosophy that I need not exist -- my existence is contingent; the universe need not exist -- there is nothing in its composition which as a quality or attribute necessitates its existence; since everything in the material realm is contingent, then its existence can only be adequately explained by an uncontingent cause, i.e., a necessary being; otherwise, if everything were contingent, we would expect nothing to exist.

"If an object has a property to a lesser extent (such as, e.g., 'goodness'), then there exists some other object that has the property to the maximum possible degree."

I disagree... there is no "maximum goodness" for instance, as what is "good" is subjective. You think religion is good for instance.

* You are entitled to disagree with this; it's a bit of a subtle, intuitive argument. Still most humans have a concept of perfection in many areas, even though we may not achieve it -- for example, we can conceive of a musical piece perfectly performed, perfect pitch, etc. Where does this concept of perfection come from, and why is it apparently hard-wired in our brains. Some would, say, because there is a perfect God who put it there. It's not the kind of brain you would expect mindless evolutionary processes to cough up.

"An object that acts for an end, but does not itself have a mind, must have been created by a being that has a mind."

Why? Why does it have to have been "created" at all??

* Because of the intentionality behind acting for an end -- an end implies purpose. So, the "reason" behind everything is the divine Logos.

None of this was AT ALL convincing....

* It's more suggestive than convincing.

BallBounces said...

That fact alone however doesnt for a minute provide any basis whatsoever for any of the religions of the world--which is what I am most interested in. All of the ones I've studied exist on pretty shoddy evidence.

* For me, it was a two-step. 1. Does God exist? 2. What is he like, has he revealed himself?

These "proofs" deal with step 1.

Joe said...

The fact remains, as is made clear by others comments, that people believe what they want to believe and dis-believe what they want to dis-believe. Few if any look at the reasons for their belief. Apart from God's calling one of the biggest reasons I believe in God is because the belief makes for a more complete world view than the secular humanist alternative. Causeless Big Bang/Evolution has so many holes in it as to be unbelievable to any except the most credulous or the most virulent anti-theists. Unfortunately for most, including ardent theists, the smoke screen thrown up by the anti-theists disguised as science, results in little discernment of truth which of course weakens the theist position. As a sage once noted, "A lie travels twice around the world before the truth has laced its boots".

BallBounces said...

Joe --

"All lies and jest.
Still a man hears what he wants to hear and disregards the rest"

-- Paul Simon, The Boxer

Joe said...

Too right there RK! I used that same quote on another blog the other day. That being said I do wish that Churches would spend more time fleshing out the Christian world view and less time perpetuating their own little myths and beliefs.

Not so long ago I mentioned to a fellow Pastor that we should practice Foot Washing. He demurred saying, "We don't practice Foot Washing, we are Baptist". If such a statement weren't so sad it would be funny.

"... nothing intellectually compelling or challenging.. bald assertions coupled to superstition... woefully pathetic"