Simple question about Aquinas's first 3 proofs

alright so I’m in a discussion with an atheist and we have gotten to the point where he and I agree that a necessary being must exist. He may also agree a first cause must exist, and a unmoved mover must exist.

so if we know these things to exist, which I think is obvious how do we get from Necessary being to God, or first cause to God, or unmoved mover to God.

Aquinas doesn’t really seem to go into this he just makes a jump from these things to God.

is this a problem with his argument or am I missing something. I suspect I’m missing something.

The attributes described are attributes of God - so in essence the proofs are all ways of saying there is a “God”. Do you mean how do they show that God is the ‘Christian’ God? If so, I think you’ll need to go a bit further than the 5 proofs.

What ***else ***are you … or he … going to call the first mover/first efficient cause/self-necessary/noblest being/end-giver?

this guy claimed it was energy and matter.

but we only took into effect

first mover

first efficient cause

and self necessary

Yeah, you need to look further.

Look into Aquinas by Ed Feser. I am sure he even references where in certain texts you will find how Aquinas works this all out. In fact, the book is just superb all in all. If your friend is serious and interested, get him/her this book.

Good question. There are two things to remember about St Thomas’ five ways. First of all, they are demonstrations of the reasonableness of faith. You cannot build a picture of the revealed God from the level of natural reason alone. In other words, we cannot establish God and all the Divine Names by moving from created effects to cause simply. The subject matter which examines ‘God’ is formally established only through Divine Revelation (ST Ia, q1. a4). So the five proofs, as St Thomas says clearly, are first and foremost about showing that faith is also reasonable and are what he calls ‘preambles’ to faith. To put it another way, you cannot argue or reason your way through natural reason to all the same conclusions provided for by Revelation. Natural reason for example could never arrive at knowledge of the Trinity unaided (Ia, q32, a1). So natural reason only takes us so far (Ia, q1, a1, ad4) but far enough for us to see that Revelation also makes sense to natural reason. Secondly, it is when we accept revelation that we see that what is revealed is also reasonable (ST Ia, q12, a12). What is revealed to us about God is able to be subject to reason and language (otherwise we could not know it).

That said however, we can make great progress with the nature of the Unmoved Mover using natural reason. We can also, by extension, come to understand the First Mover is good, one, infinite and intelligent (SCG, Bk 1, 41-44). Since we ourselves are intelligences, it follows that the cause of intelligence must itself be intelligent since no effect can be greater than its cause. Furthermore, an unmoved mover must be unmoved absolutely; that is, it cannot move ‘randomly’, since then it is subject to a motion outside of itself. It’s own motion must therefore be self-directed. So an energy force field doesn’t quite cut it as a proper designation for a first Necessary and Efficient Cause.

So in a nutshell, Aquinas does not make a leap from Unmoved Mover to the God of Christianity. He moves from the five ways to the intelligence and goodness of God, then on to God as revealed. The two positions cohere.

Oh, he meant the all-powerful all-knowing always-existing whatever it was that created the universe? LOL … see why St Thomas’ last line in each of those arguments is “and such is what people call ‘God’”?

As NewsTheMan said, Edward Feser’s work on Aquinas is highly recommended. As Dr. Feser pointed out, the five proofs only work as a whole. Continue the discussion into the 4th and 5th proofs, these two are critical and vastly misinterpreted especially by atheists. The first three were the cosmological proofs but 4th being the henological proof and the 5th being the teleological proof must be presented, so don’t forget them. Since he draws the conclusion that it was a non-intelligent entity that created, the 4th and 5th proofs will put that into question, but more importantly go over the 3rd proof again and ask why an unintelligent thing created unnecessary beings.

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