1.5.1

The Ontological Argument

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A Priori Arguments

Arguments based on reason are valid a priori, without the need to refer to observations from experience.

Illustrative background for *A priori* argumentsIllustrative background for *A priori* arguments ?? "content

A priori arguments

  • A priori arguments are simply logically true in the same way that the following argument is logically true:
    • All men are mortal;
    • Socrates is a man;
    • Therefore, Socrates is mortal.
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A priori = true by definition

  • A priori arguments are true by definition - in the same way that 2 & plus;2 = 4 is true by definition as another way of defining 2 + 2 is to call it 4.
  • If it can be shown that God exists by definition, then a priori arguments work.

The Ontological Argument

The argument is known in different forms. The generally accepted classical formulation is from Anselm (1033-1109). It is found in chapters 2-4 of his work Proslogion.

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Logical deductive argument

  • The logical demonstration in the argument either totally succeeds or totally fails – it is a logical deductive argument.
Illustrative background for Anselm’s argument (1st form)Illustrative background for Anselm’s argument (1st form) ?? "content

Anselm’s argument (1st form)

  • God is that which nothing greater can be conceived (call this ABC).
  • Even the atheist can have this definition in his understanding.
  • But if he has it in his understanding (ie in the mind) only, then there must be a greater being who exists both in the mind and reality (it is greater to exist both in the mind and reality).
  • So, by the definition ABC, God must exist both in the mind and in reality.
Illustrative background for Self-contradiction (1st form)Illustrative background for Self-contradiction (1st form) ?? "content

Self-contradiction (1st form)

  • Another way of saying this is that it is self-contradictory to be capable of conceiving something that nothing greater can be thought, and at the same time to deny that something really exists.
Illustrative background for Anselm’s Argument (2nd form)
Illustrative background for Anselm’s Argument (2nd form)
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Anselm’s Argument (2nd form)

  • The second form of the argument is developed to show the impossibility of conceiving of God as not existing.
  • God cannot not be. Any lesser form of existence where it was possible not to be would not fit with the definition of God.
Illustrative background for Theory of the 2nd form Illustrative background for Theory of the 2nd form  ?? "content

Theory of the 2nd form

  • God is ABC (see 1st form).
  • It is greater to be a necessary being than a contingent being.
  • If God exists only contingently, it would be possible to imagine a greater being who exists necessarily.
  • But if God is ABC, then that being has to be God
  • So God must be a necessary being and exist in reality.
    • It is important to note that this is logical necessity and not factual necessity (the kind of necessity arrived at in the cosmological argument).

Jump to other topics

1Philosophy of Religion

1.1Ancient Philosophical Influences: Plato

1.2Ancient Philosophical Influences: Aristotle

1.3Ancient Philosophical Influences: Soul, Mind, Body

1.4The Existence of God - Arguments from Observation

1.5The Existence of God - Arguments from Reason

1.6Religious Experience

1.7The Problem of Evil

1.8The Nature & Attributes of God

1.9Religious Language: Negative, Analogical, Symbolic

1.10Religious Language: 20th Century Perspective

2Religion & Ethics

3Developments in Christian Thought

3.1Saint Augustine's Teachings

3.2Death & the Afterlife

3.3Knowledge of God's Existence

3.4The Person of Jesus Christ

3.5Christian Moral Principles

3.6Christian Moral Action

3.7Development - Pluralism & Theology

3.8Development - Pluralism & Society

3.9Gender & Society

3.10Gender & Theology

3.11Challenges

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