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PROOF OF GOD'S EXISTENCE

THOMAS AQUINAS' FIVE WAYS OF PROVING THE EXISTENCE OF GOD

The First Way: Argument from Motion

  1. Our senses prove that some things are in motion.
  2. Things move when potential motion becomes actual motion.
  3. Only an actual motion can convert a potential motion into an actual motion.
  4. Nothing can be at once in both actuality and potentiality in the same respect (i.e., if both actual and potential, it is actual in one respect and potential in another).
  5. Therefore nothing can move itself.
  6. Therefore each thing in motion is moved by something else.
  7. The sequence of motion cannot extend ad infinitum.
  8. Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.

The Second Way: Argument from Efficient Causes

  1. We perceive a series of efficient causes of things in the world.
  2. Nothing exists prior to itself.
  3. Therefore nothing [in the world of things we perceive] is the efficient cause of itself.
  4. If a previous efficient cause does not exist, neither does the thing that results (the effect).
  5. Therefore if the first thing in a series does not exist, nothing in the series exists.
  6. If the series of efficient causes extends ad infinitum into the past, for then there would be no things existing now.
  7. That is plainly false (i.e., there are things existing now that came about through efficient causes).
  8. Therefore efficient causes do not extend ad infinitum into the past.
  9. Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.

The Third Way: Argument from Possibility and Necessity (Reductio argument)

  1. We find in nature things that are possible to be and not to be, that come into being and go out of being i.e., contingent beings.
  2. Assume that every being is a contingent being.
  3. For each contingent being, there is a time it does not exist.
  4. Therefore it is impossible for these always to exist.
  5. Therefore there could have been a time when no things existed.
  6. Therefore at that time there would have been nothing to bring the currently existing contingent beings into existence.
  7. Therefore, nothing would be in existence now.
  8. We have reached an absurd result from assuming that every being is a contingent being.
  9. Therefore not every being is a contingent being.
  10. Therefore some being exists of its own necessity, and does not receive its existence from another being, but rather causes them. This all men speak of as God.

The Fourth Way: Argument from Gradation of Being

  1. There is a gradation to be found in things: some are better or worse than others.
  2. Predications of degree require reference to the “uttermost” case (e.g., a thing is said to be hotter according as it more nearly resembles that which is hottest).
  3. The maximum in any genus is the cause of all in that genus.
  4. Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God.

The Fifth Way: Argument from Design

  1. We see that natural bodies work toward some goal, and do not do so by chance.
  2. Most natural things lack knowledge.
  3. But as an arrow reaches its target because it is directed by an archer, what lacks intelligence achieves goals by being directed by something intelligence.
  4. Therefore some intelligent being exists by whom all natural things are directed to their end; and this being we call God.

ST. ANSELM'S ONTOLOGICAL ARGUMENT

An ontological argument is a philosophical argument for the existence of God that uses ontology. Many arguments fall under the category of the ontological, and they tend to involve arguments about the state of being or existing. More specifically, ontological arguments tend to start with an a priori theory about the organization of the universe. If that organizational structure is true, the argument will provide reasons why God must exist.

Anselm defined God as "a being than which no greater can be conceived", and argued that this being must exist in the mind, even in the mind of the person who denies the existence of God.

  • He suggested that, if the greatest possible being exists in the mind, it must also exist in reality. If it exists only in the mind, then an even greater being must be possible—one which exists both in the mind and in reality. Therefore, this greatest possible being must exist in reality.

ST. AUGUSTINE OF HIPPO

The Augustinian theodicy, named for the 4th- and 5th-century theologian and philosopher Augustine of Hippo, is a type of Christian theodicy designed in response to the evidential problem of evil.

  • As such, it attempts to explain the probability of an omnipotent (all-powerful) and omnibenevolent (all-good) God amid evidence of evil in the world.
  • Augustine typically assert that God is perfectly (ideally) good; that he created the world out of nothing; and that evil is the result of humanity's original sin.
  • The entry of evil into the world is generally explained as punishment for sin and its continued presence due to humans' misuse of free will.
    • God's goodness and benevolence, according to the Augustinian theodicy, remain perfect and without responsibility for evil or suffering.
  • Augustine proposed that evil could not exist within God, nor be created by God, and is instead a by-product of God's creativity.
  • He rejected the notion that evil exists in itself, proposing instead that it is a privation of (or falling away from) good, and a corruption of nature.
  • He wrote that "evil has no positive nature; but the loss of good has received the name 'evil.'"
  • Both moral and natural evil occurs, Augustine argued, owing to an evil use of free will, which could be traced back to Adam and Eve's original sin.
  • He believed that this evil will, present in the human soul, was a corruption of the will given to humans by God, making suffering a just punishment for the sin of humans.
  • Because Augustine believed that all of humanity was "seminally present in the loins of Adam", he argued that all of humanity inherited Adam's sin and his just punishment.
  • However, in spite of his belief that free will can be turned to evil, Augustine maintained that it is vital for humans to have free will, because they could not live well without it.
  • He argued that evil could come from humans because, although humans contained no evil, they were also not perfectly good and hence could be corrupted.