Arguments Based on Reason: The Ontological Argument OCR A-Level RS Revision

An exploration of the Ontological Argument for God’s existence, focusing on a priori reasoning, Anselm, Gaunilo, Descartes and Kant.

This topic examines arguments for the existence of God based solely on reason, rather than experience or observation. It focuses primarily on the Ontological Argument, exploring classical and modern formulations, key criticisms, and its philosophical significance.

1. Introduction to Arguments Based on Reason

• Definition of a-priori reasoning (knowledge gained independently of experience)
• Contrast with a-posteriori arguments (based on observation)
• examples of deductive, inductive, analytic and synthetic arguments
• The claim that God’s existence can be deduced logically from the concept of God alone

1. Anselm’s Ontological Argument

• Anselm’s definition of God as “that than which nothing greater can be conceived”
• The distinction between existing in the mind and existing in reality
• The claim that existence in reality is greater than existence in the mind alone
• Conclusion: God must exist in reality, otherwise He would not be the greatest conceivable being

1. Anselm’s Second Formulation

• God as a necessary being rather than a contingent one
• The idea that God cannot be conceived not to exist
  -Necessary existence as a perfection

1. Gaunilo’s Criticism

• The “perfect island” objection
• Argument that Anselm’s logic could be used to prove the existence of anything perfect
• Question of whether existence can be treated as a predicate

1. Descartes’ Version of the Ontological Argument

• God defined as a supremely perfect being
• Existence as a perfection
• God’s existence follows logically from the concept of God
• Comparison to mathematical truths (e.g. triangle having three sides)
• 3 waves of doubt

1. Kant’s Critique

• Rejection of existence as a real predicate
• Argued that existence does not add a property to a concept
• Therefore, the ontological argument fails to prove God’s existence

1. Norman Malcom’s argument

• God being the ‘unlimited being’ development of Anselm’s second argument

1. Thomas Aquinas

• critique of Anselm’s ontological argument
• use of reason and observation together

1. Russell

• critique of Anselm’s ontological argument

1. Evaluation and Debate

• Strengths of a priori reasoning
• Whether existence can meaningfully be defined as a property
• Whether the argument proves anything beyond a concept
• Ongoing relevance of the ontological argument in philosophy of religion

Essay questions and guidance on how to answer