Aquinas' Cosmological Argument

• Based on motion, including movement from 1 place to another/ in the sense of change.
• When something is put in motion, a change takes place.
• There must be something which sets things in motion - 'Unmoved mover.'
• Aq explained the need for an external influence. E.g. an object moves when an external force is applied to it.
• This chain of movement cannot go back to infinity.
• There must be a first unmoved mover that began the movement in everything else without itself being moved - God.
• Aq showed how things achieve their potential through an external influence.
• Change requires actuality. E.g. the fact that wood is wood = actuality, the fact that fire can make it hot = potentiality.
• Something must have caused the fire to change and become alight.
• Therefore, each change is the result of a previous change.
• God is the actuality but he does not have potentiality bc that would mean he isn't God.
• Aq rejected an infinite series of changes bc he believed that the point when the first movement occurred was brought about by Unmoved Mover.
• This is God.

• Based on cause
• Aq identified a series of causes and effects in O.
• Nothing could be the cause of itself bc that would mean it had to exist before it existed which is a logical impossibility.
• Without cause, there would be no other effects.

• Aq rejected an infinite series of causes bc that would mean there is no first mover.
• He rejected the idea of an infinite regression of movers putting nothing into motion.
• There was a first uncaused cause that caused all other events to happen - God.
• Aq did not think that cause went back to infinity.
• To deny infinite regress means that he believed in an eternal being that was not dependant on anything else for its existence.
• Uncaused cause is God.

• Based on contingency.
• Something must have started off the O bc everything that exists in the O has a cause.
• O began to exist, therefore O must have a cause.

• Aq examined all contingent matter and the possibility of infinite time.
• If time is infinite then there must have been a time when nothing existed bc of contingency. Everything in the O is contingent which means it cannot go on forever.
• If there was nothing then there would still be nothing as nothing can bring itself into existence.
• Cause of O = eternal and has always existed.
• Aq called this the 'necessary being' - God.
• Everything in the universe has a finite conditional existence whose existence depends on an infinite unconditional cause - God.
• Every cause in the chain of causes is dependant on God for its existence.
• God = Necessary being who upholds the existence of everything.

Seeks to prove the existence of God based on the fact that there is a universe.

Cosmos = universe (O).

Developed from Aristotle's view of God as sustaining the universe

..... by Thomas Aquinas in his 'Summa Theologica' in which he devised 5 ways to prove the existence of God, the first 3 being:

• Motion
• Cause
• Contingency

It is an a posteriori argument bc it is based on what can be seen and observed.