Medieval Proofs of the Existence of God

Anselm

• Ontological Argument
  • whenever there is an offense against another party, the magnitude of the human sin is an offense against God
  • the greater the offended party, the greater the sacrifice required to satisfy the penalty
  • because God is infinite, the sacrifice must be infinite
  • the only possible infinite sacrifice is God himself
  • therefore, God must become human to identify with humans as a representative of the human race, but must remain God at the same time to satisfy the requirement of an infinite penalty

Thomas Aquinas

• Argument from motion (first mover)
• Argument from efficient cause (first cause in chain of causation)
• Argument from necessary being (without which nothing would exist, for all other beings are only possible, not necessary)
• Argument from gradation (great chain of being implies perfect being, greater in all ways than all other beings)
• Argument from governance (intelligent designer)