Key words:

  • Causality
  • Material, efficient, formal, final causes
  • Actuality
  • Potentiality
  • Teleology 
  • Intrinsic 
  • Superflous 
  • Prime Mover
  • Unmoved 
  • Empiricist 
  • A posteriori 

Aquinas' First Way to prove God exists - motion/change. Anything which is changing is being changed by something else. The first cause/mover os everything is God. 

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  • Potentality to actuality - progression from idea to reality 
  • Four Causes
    • material cause - what is it made of?
    • efficient cause - how was it made?
    • formal cause - characteristics
    • final cause - ultimate purpose 
  • Final cause is the most important 
  • Final purpose = teleology. When this is realised, an object has reached perfection and goodness
  • The purpose of an object is intrinsic - cannot be changed 
  • Nothing is superfluous 
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Why Causality?

  • Answers questions such as:
    • what does it mean for something it exist?
    • what gives particular objects their characteristics
    • what causes everything?
    • why does change occur?
    • can something have matter but no form?
    • how do things move from potentiality to actuality?
  • Knowledge is based on the physical world
  • Causes are based on empirical evidence 
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Strengths of Causality:

  • Ideas from the world of sense experience - can be verified or falsified 
  • Scientifically plausible
  • Science and God are not necessarily mutually exclusive 
  • Basis for popular ethical theories such as Natural Law and Virtue Ethics
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Weaknesses of Causality:

  • Is the material world the only source of true knowledge?
  • Little evidence for the final cause - what if things happen by blind chance?
  • Is there any purpose except existence?
  • Causality cannot be applied to the Prime Mover 
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Prime Mover:

  • Eternal substance that is immune to change
  • Causes all motion/change
  • Responsible for all things
  • Umoved, good, impersonal
  • Final cause
  • Matter without form
  • Object of love and desire for the world
  • Humans trive for the Prime Mover's perfection
  • God 
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Why Prime Mover?

  • All movement depends on a mover 
  • Final purpose of all things 
  • Change is eternal - no first change, only a changer. 
  • Unaffected
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Strengths of Prime Mover:

  • Explanations for movement and change
  • Gives ultimate purpose
  • Reason for purpose (object of love & desire)
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Weaknesses of Prime Mover:

  • Claiming God causes himself contradicts the theory of an uncaused causer 
  • Why is there a Prime Mover - why not a chain of cause and effect?
  • No one can experiece the Prime Mover
  • Aristotle claims a person's purpose is immortal and yet also says the soul dies with the body
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