How can God's existence be demonstrated by reason?

[YoungTradCath]

What are some resources that address this specifically?

I quote from the Oath Against Modernism:

God, the origin and end of all things, can be known with certainty by the natural light of reason from the created world (cf. Rom. 1:20), that is, from the visible works of creation, as a cause from its effects, and that, therefore, his existence can also be demonstrated.

How? How does the Church do this today? In proofs, documents, nifty little logical treatises?

 

[edward_george]

There are a number of arguments that philosophers and theologians have used throughout the years. Check out St. Thomas Aquinas’ Five Ways, found in Summa Theologiae I, question 2, article 3. Also, check out Dr. Peter Kreeft’s website at www.peterkreeft.com for some fantastic articles on apologetics for the existence of God using rational arguments.

-ACEGC

 

[Aquinas_Jr]

First, what is your definition of God?

 

[Aquinas_Jr]

The easiest proof is this. We can all agree that some objects are capable of undergoing motion. Everything that undergoes motion is moved by another that moves it. This “another” this “mover” is itself either moved or unmoved. If it is unmoved, then we have to posit an unmoved mover. This is what men refer to as God. If this “another” is moved, then it must be moved by something else, which must be moved by yet another onto infinity. But proceeding to infinity is impossible. Therefore, at some point, we must arrive at some First Prime unmoved mover, and this we call God. And by understanding God as the unmoved mover we can deduce many other things such that he is eternal, purely good, etc.

 

[Jon_S_1]

What are some resources that address this specifically?

I quote from the Oath Against Modernism:

How? How does the Church do this today? In proofs, documents, nifty little logical treatises?

Aquinas ’ five ways are really good…legendary

Here is a video on the proof from contingency to get you started.

youtu.be/W_Yjue8MXAI

I also like the idea of the watchmaker, that nature and the universe are ordered functional and appear designed thus there must be a designer.

It would be like a primitive person walking through the forest and they see a watch and pick it up. Without any concept of time or mechanics or metal smithing or gears they could look at this object and know it was no accident. That it was designed for a purpose.

So too do we look at creation.

 

[Bagheera]

YoungTradCath:

God, the origin and end of all things, can be known with certainty by the natural light of reason from the created world (cf. Rom. 1:20), that is, from the visible works of creation, as a cause from its effects, and that, therefore, his existence can also be demonstrated.

I am always amused that no one points out the logical incoherence of this sentence. It uses the phrase of “created world”. So effectively it says: “This world is created. A created world needs a creator. The creator is God. Therefore we have a “rational” demonstration of God. What a wonderful example of circular “reasoning”!

There are a whole lot of alleged proofs of God’s existence. None of them stand up to the scrutiny of reason, and probably the church realizes this, since the church does not endorse any one of them as being the “best, fully acceptable **official **proof”. Moreover, if there would be a truly foolproof, rational method to demonstrate God’s existence, then “faith” would not be necessary any more.

Hundreds of (abbreviated) proofs here!!

 

[tstrong728]

I am always amused that no one points out the logical incoherence of this sentence. It uses the phrase of “created world”. So effectively it says: “This world is created. A created world needs a creator. The creator is God. Therefore we have a “rational” demonstration of God. What a wonderful example of circular “reasoning”!

There are a whole lot of alleged proofs of God’s existence. None of them stand up to the scrutiny of reason, and probably the church realizes this, since the church does not endorse any one of them as being the “best, fully acceptable **official **proof”. Moreover, if there would be a truly foolproof, rational method to demonstrate God’s existence, then “faith” would not be necessary any more.

Hundreds of (abbreviated) proofs here!!

I don’t think it’s circular to state the obvious. God created the world, if He didn’t then we wouldn’t be here. We’re here, that proves God does exist.

A truly circular argument is “If God existed you could prove he existed to everyone, but since there is one atheist who refuses to believe that God exists He must not exist.” As if not proving God exists is proof that He doesn’t exist.

True Faith is about much more than simply accepting that God exists or that He created the world.

 

[Mount_Carmel]

It is in the ‘nitty gritty’ details of God that most atheist ‘scientist’ types have problems with.
Most seem to understand that there must be an acaused origin to all that is, and that this origin must be able to create/make the likes of physical and temporal substance out of/from that which pre-existed it. They would tend to agree that ‘nothing’ cannot cause ‘something’ from ‘nothing’. That physical and temporal existence alone cannot rationally support its own reality, that there needs to be other ‘stuff’ that is involved in the existence of the universe and all contained therein. That infinity and eternity appear incompatible with the physical and temporal, and that the link between the two appears to be beyond the ken of physical and temporal ‘five senses’ science alone.

You may also suggest that the likes of ‘chaos’ might appear so because the lack of our complete knowledge of what is actually going on. That if we knew and understood all that happens it would appear more as ‘cause(s) and effect(s)’. You could also point out that 'cause(s) must be greater than ‘effect(s)’, since if this was not so we would have stasis/status quo. You might also point to the likelihood that that the ‘acaused’ start point needs be greater than all the follow on.

Enjoy the mental exercise, I hope it bears fruit.

 

[Theophorus]

I am always amused that no one points out the logical incoherence of this sentence. It uses the phrase of “created world”. So effectively it says: “This world is created. A created world needs a creator. The creator is God. Therefore we have a “rational” demonstration of God. What a wonderful example of circular “reasoning”!

There are a whole lot of alleged proofs of God’s existence. None of them stand up to the scrutiny of reason, and probably the church realizes this, since the church does not endorse any one of them as being the “best, fully acceptable **official **proof”. Moreover, if there would be a truly foolproof, rational method to demonstrate God’s existence, then “faith” would not be necessary any more.

Hundreds of (abbreviated) proofs here!!

The phrase ‘created reality/created world’ presupposes you are familiar with the arguments as to why matter/the universe cannot be self-sustaining from a metaphysical point of view. It is not used as a logical first principle in a circular argument.

The first argument in the chain is that everything in motion must have been put in motion, that stuff doesn’t ‘just happen’. From this we get to dependant reality, then the question becomes what is it dependent on? Once we establish that there must be a prime mover/first cause then we examine what this is. We move from the effects to the cause, that is not a circular argument.

 

[Theophorus]

What are some resources that address this specifically?

I quote from the Oath Against Modernism:

How? How does the Church do this today? In proofs, documents, nifty little logical treatises?

For a background I would start by reading * Dei Filius * from Vatican I especially chapter 4 on faith and reason

There is of course philosophical investigation. The perennial philosophy does this by proceeding from the effects to the cause(St. Thomas does this very well and is still relevant today especially in his five ways in the Summa Theologicae and the corresponding section in the Summa Contra Gentiles)

I hope that is of help

 

[Bagheera]

Theophorus:

The phrase ‘created reality/created world’ presupposes you are familiar with the arguments as to why matter/the universe cannot be self-sustaining from a metaphysical point of view.

Which “metaphysical” point of view? From mine it certainly is.

Theophorus:

It is not used as a logical first principle in a circular argument.

Formally it is, since it is not followed by some reasoning. At best it is nothing but an unsubstantiated starting point. And as such – worthless.

For a really rational argument the apologist needs to start with the null-hypothesis that the universe is “everything that exists”. Then he needs to bring up a physical (not some metaphysical!) feature, which cannot be explained by the null-hypothesis. The argument from motion (for example) does not work. Motion or change are inherent features of the universe. There is no need to assume an “electron-pusher”, who started the movements of the electrons (much less an electron-donkey, who keeps dragging them along on their paths). Motion and change need no “external” explanation. Not to mention that the concept of “external” is at least problematic (or downright incoherent).

But, suppose that the apologist is able to show a physical feature (let’s call it “X”), which logically points to some “external” causative factor. That would be an enormous achievement, but still not sufficient. The apologist then would need to show how that external factor could “influence” the physical reality in order to explain that feature of “X”. (To say: “let there be light and there was light” is not an explanation.) In other words, he needs to show the “epistemological” foundation of his reasoning. (Again: “revelation” does not cut it.) And if he could do all that, then it still would not lead to the personal God of Christianity. At best it would lead to an impersonal, deistic first cause.

All those alleged “proofs” by Aquinas et al. do nothing of this kind. They all start with a “no black swan” fallacy, and go downhill from there.

 

[Paddy_Walker]

Maybe the best proof is that it cannot be proven. Something with that degree of resilience, that it has never been proven nor disproven, has a lot going for it.

 

[Linusthe2nd]

" The most manifest way is through motion. " This is the First Way of Thomas Aquinas which was given in three forms in the S.T., the S.C.G., and the Compendium of Theology. I have started a thread on the First Way called " The First Way Explained, " on this forum. Everyone can take a look, it is a work in progress and will not be completed for a month or two because of the research I am doing on it. It is my intention to explain how it is perfectly compatible with modern science. It is also my intention to correct some errors in interpretation which have caused confusion, even among Thomists. I proceed through the device of " Lessons " and occassional comments between " Lessons. "

Linus2nd

 

[HardRockGTR]

The easiest proof is this. We can all agree that some objects are capable of undergoing motion. Everything that undergoes motion is moved by another that moves it. This “another” this “mover” is itself either moved or unmoved. If it is unmoved, then we have to posit an unmoved mover. This is what men refer to as God. If this “another” is moved, then it must be moved by something else, which must be moved by yet another onto infinity. But proceeding to infinity is impossible.

Why?

Therefore, at some point, we must arrive at some First Prime unmoved mover, and this we call God.

Who is said to be infinite, which you just said was impossible.

And by understanding God as the unmoved mover we can deduce many other things such that he is eternal, purely good, etc.

Why?

 

[Genesis315]

Moreover, if there would be a truly foolproof, rational method to demonstrate God’s existence, then “faith” would not be necessary any more.

That’s not what faith is. Faith is not a blind guess or a feeling. Faith is believing what God has revealed on only the authority of God the revealer. Faith therefore presumes one can determine God exists and can also determine what He has revealed–faith is the assent to that revelation.

For example, by faith we believe that the Second Person of the Trinity is present in the Holy Eucharist because He has said He is and there is no other way to know.

 

[HardRockGTR]

I don’t think it’s circular to state the obvious. God created the world, if He didn’t then we wouldn’t be here. We’re here, that proves God does exist.

That’s pretty circular to me. Unless, of course, your definition of “God” is the most loose one possible.

 

[QNDNNDQDCE]

That’s pretty circular to me. Unless, of course, your definition of “God” is the most loose one possible.

It would be circular if it were intended as a demonstration and not an assertion. That was Bagheera’s criticism, that the statement was “logically incoherent” because it assumed that the universe was created rather than demonstrating it philosophically. It would be as though I had asserted that the non-existence of a highest prime number could be known by reason through the factorability of a highest prime number, and Bagheera barged in and started prattling on about how I was begging the question by assuming that a highest prime number would be factorable, as if I intended my statement as a rigorous demonstration rather than the assertion of a fact and a summary of one argument that proves it.

 

[HardRockGTR]

Maybe it’s because I’m sleepy, but your inclusion of mathematics only confuses me more

 

[QNDNNDQDCE]

All I meant was that the statement from the First Vatican Council quoted in the first post (which Bagheera was attacking) was not intended as a rigorous demonstration!

 

[Bagheera]

qndnndqdce:

All I meant was that the statement from the First Vatican Council quoted in the first post (which Bagheera was attacking) was not intended as a rigorous demonstration!

In which case it is an ill-formed (circular) and baseless assertion. It is revealing that the church never came and provided an official and rigorous demonstration of “how” can God’s existence be known by reason alone. I already provided the frame of how this should be done in post #11.