The cosmological argument for the existence of God

Fast facts

• Cosmology is from the Greek word cosmos, meaning universe or world
• The cosmological argument is an a posteriori argument for the existence of G/d
• Advocates include Thomas Aquinas, Maimonides and Frederick Copleston
• Critics include David Hume

Pisp.co.uk

Welcome to the cosmological argument

See footnotes for licence[1]

The cosmological argument can be traced right back to the dawn of philosophy in Ancient Greece. But, the most famous version comes from every Catholic’s hero: Thomas Aquinas (see right). Aquinas wrote in the 13th century and is the guy behind most of the Roman Catholic Church’s theology – even today. Cosmology aims to prove G/d’s existence by using the world around us, our a posteriori experience. This is unlike the ontological argument, which aims to prove G/d’s existence by moving from a definition of G/d to the concept of G/d.

What is cosmology?

Well, and I know we open with this every time, but it’s all in the name. Cosmology is from the Greek word κοσμολογία, meaning world or universe. So, cosmology is all about using the world around us as a proof for G/d’s existence.

Quinque viae (five ways)

Aquinas' argument for the existence of came in a bundle of five different arguments, known as the quinque via -- Latin for 'five ways'.

Who was Thomas Aquinas?

All you need to know about Thomas Aquinas in four easy-to-remember bullet points:

• He was a Dominican friar
• He lived during the 13th century
• He was influenced by Aristotle
• He put forward the Cosmological Argument in Summa Theologica

Prima via (first way)

First, we'll introduce the two arguments in premise form. Don't worry if you don't get all of what was said, we'll deal with the explanations later.

Secundum via (second way)

Under the influence of Aristotle: the unmoved mover

See footnotes for licence[2]

Aristotle (see right) believed that there was an unmoved mover who caused all movement in the world with the intention of moving to perfection. Was Aristotle not dead at the time, I’m sure he’d have claimed copyright infringement since Aquinas’ definition of G/d sounds an awful lot like a rebranded unmoved mover!

Actus et potentia (Actuality and potentiality)

This is a concept you'll need to get your head around if you're going to make any sense of cosmology. It can seem a little confusing, but it’s easy once you get the hang of it!

Do you remember process diagrams from Key Stage 2 maths? There would be three boxes; marked ‘input’, ‘process’ and ‘output’, and then you'd be given numbers in two of those boxes. It’d be your task to work out the missing number. So, an input of 2 and a process of x3 gives an output of 6. In the same way, an input of 2 and an output of 6 gives a process of x3. Where am I going with this? Well, you can do the same with cosmology! Check this out...

What's the difference?

Still struggling? All objects possess act and potential, or potency. Act and potency are essentially opposing states.

We use wood to make fires, but a block of wood itself won't burn. We can say it has the potential to burn. Its potentiality to burn is actualised when it is moved to a source of heat.

Wood can burn, but it can’t possess the potential to burn and be burning at the same time... it’s logically impossible. When the wood is burning, it is a realisation of the wood’s potential to burn.

Aristotle's legacy again: the efficient cause

Yet more evidence of Aquinas pilfering ideas from Aristotle! The efficient cause is the agent which brings something about.

Let's just pretend that my college has commissioned a statue of me to be built at the entrance, because I’m so great. In this case, the person chiselling away at the marble, and the act of chiselling itself, is the efficient cause because it causes the statue.

WWW: IR?

According to Aquinas, we need a being that is actus purus (pure act) that is only in a state of actuality and has never been potentiality to make sense of our existence. He rejects a series of infinite causes, believing that there must be a first cause -- the being of pure act, God.

But, by rejecting infinite regression, Aquinas’ argument is flawed.

• His conclusions thus far state that there is a first cause/mover, but the premises state everything must have a cause. How’s that working?
• Even if we get over that quite glaring flaw, what’s to say that the first cause/mover that Aquinas talks of still exists today? My father’s granddad and grandma are dead, but my father’s parents and my father are still here.

David Hume puts a spanner in the works

See footnotes for license[3]

He wasn't alive at the same time as Aquinas, but David Hume raised a very valid point: must every event have a cause?

For Hume, it’s not an analytic truth... the only way we can know that every event has a cause is if we verify it using our experience. We have no experience of the beginning of the universe, so this can’t happen.

Tag: Copleston

Aquinas isn't speaking of a horizontal series of causes:

But instead of a vertical hierarchy of causes:

Cause in fieri and in esse

Cause in fieri Children can exist separately of their parents, like single-parent families. Despite this, their parents are required for their cause.	Cause in esse Activity of the pen cannot exist separately of the hand writing. The hand is required for both the cause and to sustain the cause.

Contingency and necessity

This brings us nicely to contingency and necessity.

• Something that is necessary relies on itself alone for existence.
• Something that is contingent requires other factors for its existence.

Copleston's argument in premises

Let's make sure we understand it by breaking it down into premises.

P1	Everything in the universe is contingent and might not have been.
P2	The universe, then, is the totality of all contingent things and is itself contingent.
P3	Following that, the necessary cause of the universe must be outside of it.
P4	Therefore, there exists a necessary being that sustains all contingent beings.

Tertia via: contingency and necessity

Prima pars (first part)

Secundum pars (second part)

Note the two parts to this proof

• Aquinas was writing in the 13th – 14th centuries, where people believed in the existence of Angels.
• The Nine Orders of Angels are necessary, so had he stopped after the first part, it would have been reasonable to accept that an angel could have created the universe.

De re and de dicto beings

In the last argument, a new term was introduced: de re. De re and de dicto are simply words to describe necessary beings, one of which is called into existence and the other which 'just exists'.

The third way is like a padlock

Aquinas’ third way conveniently locks his arguments so far into place, binding them to form a proof.

• Nothing can move/cause G/d.
• Nothing can move/cause G/d’s non-existence.
• Nothing that moves/causes can be accounted for without G/d.

Final thoughts

Pisp.co.uk

Cite this article

• The MLA (Modern Language Association) format is most commonly used to write papers and cite sources within the liberal arts and humanities.
• The Harvard style is the most commonly-used style of referencing worldwide; we use the British Standards recommended variant.
• If your format is not listed, we've given a list of article details that you can compile to make your own.

MLA format

Harvard format (BSI)

Other formats

Here are some article details you may use to compile a reference in another format.

• Author: Pisp.co.uk
• Title: The Cosmological Argument for the Existence of God
• Publisher: Pisp.co.uk
• Place of publication: Birmingham, UK
• Date published: Friday, 23 January 2009
• URL: http://www.pisp.co.uk/learn/por/cosmology.htm