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27 Dec 2025
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Understanding Aquinas' Cosmological Argument
bella
@be1laxx
1 / 8
The Cosmological Argument Background
Aquinas wasn't just making wild guesses about God's existence. His approach was methodical and evidence-based, following the principle that "one must proportion his belief to his evidence." The word 'cosmological' comes from 'cosmos', referring to our space-time universe.
Unlike other arguments for God's existence, Aquinas used an inductive and a posteriori approach. This means he started with observations of the real world rather than pure logic. He noticed that everything around us seems to depend on something else for its existence.
The heart of his argument rests on rejecting infinite regress - the idea that causes could go back forever without a starting point. Think of dominoes falling: something must have pushed the first one, or the chain never begins.
Key Point: Aquinas believed there must be a necessary being (something that cannot not exist) to explain why contingent things (things that could exist or not exist) are here at all.
The Third Way Explained
Aquinas structured his Third Way as a logical sequence that's surprisingly easy to follow. He starts with a simple observation: everything in the natural world is contingent - it exists, but it doesn't have to exist.
Here's his reasoning: if everything is contingent, then at some point there was nothing at all. But "ex nihilo nihil fit" - out of nothing, nothing comes. Since something clearly exists now, there must be a necessary being that couldn't fail to exist.
Aquinas then tackles an important objection. What if necessary things exist, but they're all caused by other necessary things? His answer: this creates another infinite chain, which explains nothing. There must be an uncaused necessary being at the foundation.
This uncaused necessary being, according to Aquinas, is what we call God. It's the anchor that prevents the whole system from collapsing into meaningless infinite regress.
Think About It: Imagine a bicycle wheel - if you remove the central hub, all the spokes collapse. Aquinas sees God as the essential "hub" of existence.
Major Criticisms of Aquinas
Bertrand Russell delivered some of the strongest criticisms of Aquinas' argument, particularly through his famous debate with F.C. Copleston. Russell's main weapon was the fallacy of composition - just because parts have a quality doesn't mean the whole does.
Russell argued that even if everything in the universe is contingent, the universe itself might not be contingent. It's like saying every human has a mother, therefore the human race has a mother - clearly faulty logic.
David Hume and Kant attacked from a different angle. They insisted that all claims about existence must be synthetic - verifiable through sense experience. Aquinas, they argued, simply assumed God's necessary existence without proper evidence.
William of Ockham's Razor suggests we should favour theories with the fewest assumptions. Why assume God when the universe's existence might simply be a brute fact - something that just is, with no explanation needed?
Russell's Challenge: "The universe is just there, and that's all" - sometimes the simplest explanation is that there isn't one.
The Value and Limitations of Aquinas' Argument
For believers, Aquinas' argument provides enormous value by putting faith into reason. It shows that religious belief doesn't have to abandon logic - instead, it can use philosophical thinking to support theological understanding.
The argument's basic idea remains accessible despite its technical language. Most people can grasp that our contingent universe might need a necessary foundation - it connects with our everyday experience of cause and effect.
However, modern philosophers like R.M. Hare suggest we all operate with 'bliks' - fundamental worldviews that can't be changed by arguments. If this is true, then Aquinas' Christian 'blik' might prevent him from seeing alternatives, just as an atheist's 'blik' prevents them from accepting God.
Gerry J. Hughes offers a more optimistic view, arguing that we should expand our idea of 'proof' beyond pure logic to include probability - much like science does. Perhaps Aquinas doesn't need to provide absolute certainty, just reasonable likelihood.
Food for Thought: Is it better to have a probable explanation (God) or accept that some things (like existence itself) might be permanently unexplainable?
We thought you’d never ask...
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Understanding Aquinas' Cosmological Argument
bella
@be1laxx
Ever wondered why the universe exists? Thomas Aquinas, a 13th-century Catholic theologian, tackled this massive question with his cosmological argument - a logical attempt to prove God's existence based on what we observe around us.
The Cosmological Argument Background
Aquinas wasn't just making wild guesses about God's existence. His approach was methodical and evidence-based, following the principle that "one must proportion his belief to his evidence." The word 'cosmological' comes from 'cosmos', referring to our space-time universe.
Unlike other arguments for God's existence, Aquinas used an inductive and a posteriori approach. This means he started with observations of the real world rather than pure logic. He noticed that everything around us seems to depend on something else for its existence.
The heart of his argument rests on rejecting infinite regress - the idea that causes could go back forever without a starting point. Think of dominoes falling: something must have pushed the first one, or the chain never begins.
Key Point: Aquinas believed there must be a necessary being (something that cannot not exist) to explain why contingent things (things that could exist or not exist) are here at all.
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The Third Way Explained
Aquinas structured his Third Way as a logical sequence that's surprisingly easy to follow. He starts with a simple observation: everything in the natural world is contingent - it exists, but it doesn't have to exist.
Here's his reasoning: if everything is contingent, then at some point there was nothing at all. But "ex nihilo nihil fit" - out of nothing, nothing comes. Since something clearly exists now, there must be a necessary being that couldn't fail to exist.
Aquinas then tackles an important objection. What if necessary things exist, but they're all caused by other necessary things? His answer: this creates another infinite chain, which explains nothing. There must be an uncaused necessary being at the foundation.
This uncaused necessary being, according to Aquinas, is what we call God. It's the anchor that prevents the whole system from collapsing into meaningless infinite regress.
Think About It: Imagine a bicycle wheel - if you remove the central hub, all the spokes collapse. Aquinas sees God as the essential "hub" of existence.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Major Criticisms of Aquinas
Bertrand Russell delivered some of the strongest criticisms of Aquinas' argument, particularly through his famous debate with F.C. Copleston. Russell's main weapon was the fallacy of composition - just because parts have a quality doesn't mean the whole does.
Russell argued that even if everything in the universe is contingent, the universe itself might not be contingent. It's like saying every human has a mother, therefore the human race has a mother - clearly faulty logic.
David Hume and Kant attacked from a different angle. They insisted that all claims about existence must be synthetic - verifiable through sense experience. Aquinas, they argued, simply assumed God's necessary existence without proper evidence.
William of Ockham's Razor suggests we should favour theories with the fewest assumptions. Why assume God when the universe's existence might simply be a brute fact - something that just is, with no explanation needed?
Russell's Challenge: "The universe is just there, and that's all" - sometimes the simplest explanation is that there isn't one.
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The Value and Limitations of Aquinas' Argument
For believers, Aquinas' argument provides enormous value by putting faith into reason. It shows that religious belief doesn't have to abandon logic - instead, it can use philosophical thinking to support theological understanding.
The argument's basic idea remains accessible despite its technical language. Most people can grasp that our contingent universe might need a necessary foundation - it connects with our everyday experience of cause and effect.
However, modern philosophers like R.M. Hare suggest we all operate with 'bliks' - fundamental worldviews that can't be changed by arguments. If this is true, then Aquinas' Christian 'blik' might prevent him from seeing alternatives, just as an atheist's 'blik' prevents them from accepting God.
Gerry J. Hughes offers a more optimistic view, arguing that we should expand our idea of 'proof' beyond pure logic to include probability - much like science does. Perhaps Aquinas doesn't need to provide absolute certainty, just reasonable likelihood.
Food for Thought: Is it better to have a probable explanation (God) or accept that some things (like existence itself) might be permanently unexplainable?
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Sign up to see the contentIt's free!
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Sign up to see the contentIt's free!
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Sign up to see the contentIt's free!
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We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
Where can I download the Knowunity app?
You can download the app from Google Play Store and Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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Most popular content: Cosmological Argument
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Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.9/5
App Store
4.8/5
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user