Aquinas five ways
Posted: Tue Nov 21, 2017 1:38 pm
There have been lot of discussions about Aquinas five ways but I have had problems to follow the arguments. Therefore I would like to discuss them more thoroughly and I start with the second way.
Aquinas original text if found here http://web.mnstate.edu/gracyk/courses/w ... veWays.htm
and here is a systematisation that I found useful:
http://web.mnstate.edu/gracyk/courses/w ... alysis.htm
As far as I can see it follows Aquinas text well.
This is an extract from the latter:
The Second Way: Argument from Efficient Causes
1. We perceive a series of efficient causes of things in the world.
2. Nothing exists prior to itself.
3. Therefore nothing [in the world of things we perceive] is the efficient cause of itself.
4. If a previous efficient cause does not exist, neither does the thing that results (the effect).
5. Therefore if the first thing in a series does not exist, nothing in the series exists.
6. If the series of efficient causes extends ad infinitum into the past, for then there would be no things existing now.
7. That is plainly false (i.e., there are things existing now that came about through efficient causes).
8. Therefore efficient causes do not extend ad infinitum into the past.
9. Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.
My comments:
If you think that the Universe is infinite old then 5. is wrong. It's just about definitions. In an infinite series there is by definition no last object (e.g. the series of whole numbers increasing from 1 upwards) or no first object (e.g if the series increasing from minus infinitive to -1). If an infinite series of efficient causes extends ad infinitum to the past then every element has a preceding efficient cause so 4. is irrelevant and 5 does not follow.
I know that somebody claim that actual infinite series are impossible and then 5. is true, but that's just another premise that can be discussed. I don't see any argument for that premise.
If you think that the Universe isn't infinite old then clause 5 could be true and the wave is correct besides clause 9, the last part. We have to admit a First Efficient Cause (an FEC) but we don't have to call that entity God. We could call the FEC anything, for instance a Multiverse.
Then we can discuss the features of the FEC. Some say that the FEC has to be simple, omnipotent, all knowing, etc (being God) but I have not seen any argument for that. It could as well be simple and only able to create Universes but nothing more (being a Multiverse). The second wave gives no argument for choosing that the FEC is God instead of some other entity. It just states that everyone think that it is (given the name) God. That statement may have been reasonable in the 13th century but not today.
Then again we can discuss what is most probable, God, Multiverse or any other FEC but that is another discussion where we have to bring in all arguments from our respective worldviews. It would be nice if we could concentrate on Aquinas original argument in this thread.
Nils
Aquinas original text if found here http://web.mnstate.edu/gracyk/courses/w ... veWays.htm
and here is a systematisation that I found useful:
http://web.mnstate.edu/gracyk/courses/w ... alysis.htm
As far as I can see it follows Aquinas text well.
This is an extract from the latter:
The Second Way: Argument from Efficient Causes
1. We perceive a series of efficient causes of things in the world.
2. Nothing exists prior to itself.
3. Therefore nothing [in the world of things we perceive] is the efficient cause of itself.
4. If a previous efficient cause does not exist, neither does the thing that results (the effect).
5. Therefore if the first thing in a series does not exist, nothing in the series exists.
6. If the series of efficient causes extends ad infinitum into the past, for then there would be no things existing now.
7. That is plainly false (i.e., there are things existing now that came about through efficient causes).
8. Therefore efficient causes do not extend ad infinitum into the past.
9. Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.
My comments:
If you think that the Universe is infinite old then 5. is wrong. It's just about definitions. In an infinite series there is by definition no last object (e.g. the series of whole numbers increasing from 1 upwards) or no first object (e.g if the series increasing from minus infinitive to -1). If an infinite series of efficient causes extends ad infinitum to the past then every element has a preceding efficient cause so 4. is irrelevant and 5 does not follow.
I know that somebody claim that actual infinite series are impossible and then 5. is true, but that's just another premise that can be discussed. I don't see any argument for that premise.
If you think that the Universe isn't infinite old then clause 5 could be true and the wave is correct besides clause 9, the last part. We have to admit a First Efficient Cause (an FEC) but we don't have to call that entity God. We could call the FEC anything, for instance a Multiverse.
Then we can discuss the features of the FEC. Some say that the FEC has to be simple, omnipotent, all knowing, etc (being God) but I have not seen any argument for that. It could as well be simple and only able to create Universes but nothing more (being a Multiverse). The second wave gives no argument for choosing that the FEC is God instead of some other entity. It just states that everyone think that it is (given the name) God. That statement may have been reasonable in the 13th century but not today.
Then again we can discuss what is most probable, God, Multiverse or any other FEC but that is another discussion where we have to bring in all arguments from our respective worldviews. It would be nice if we could concentrate on Aquinas original argument in this thread.
Nils