Lecture on Natural Theology and Critique by Immanuel Kant

Thomas Aquinas and Natural Theology

• Thomas Aquinas's approach to natural theology:
  • Reaction to the Aristotelianism of Muslim philosophy (double truth theory)
  • Constructed the "Classical Synthesis": showing that both philosophy and theology reveal the truth of God's existence
  • Intellectual climate: rare to challenge the existence of God

Principal Arguments for the Existence of God

1. Ontological Argument
   • Origin: Formulated early by Augustine, popularized by Saint Anselm
   • Argument from being
2. Cosmological Argument
   • Reasoned from the world (cosmos) to its origin (Creator)
   • Based on causality: transcendent cause for the universe
3. Teleological Argument
   • Argument from design (Greek word 'telos' meaning end/purpose)
   • Presence of design in the universe indicates a Designer
4. Moral Argument
   • Recognized but not detailed in this lecture

• Dominance of Christianity in medieval academic world
  • Theology as "queen of sciences," philosophy as "handmaiden"

Immanuel Kant's Critique

• Impact on Classical Synthesis
  • "Critique of Pure Reason" (late 18th century)
  • Revolutionary impact on intellectual history
• Motivations and Outcomes
  • Motivated by rescuing science from skepticism (influenced by David Hume)
  • Critiqued traditional arguments for God's existence, not denying God but questioning natural reason
• Kant's Epistemological Framework
  • Phenomenal Realm: World of appearances perceived by senses
  • Noumenal Realm: World of essences (God, self, 'thing-in-itself') beyond sensory perception
  • Unbridgeable chasm: Reason/science confined to the phenomenal; cannot access noumenal

Kant’s Influence and Theological Response

• Shift in Christian apologetics post-Kant
  • Development of Fideism: Taking God's existence on faith, not through reason
  • Some theologians rejected Kant, sought to revise natural theology
• Kant vs. New Testament
  • Conflict with Apostle Paul’s teaching (Romans 1): Knowledge of God evident in creation
  • Kant: No certain knowledge of God through reason, contradicting biblical assertion

The Ontological Argument and Its Critics

• Anselm's Formulation

  • God as the greatest conceivable being, must exist in reality

• Kant's Critique

  • Existence is not an attribute; hypothetical vs. real being
  • Debate over validity continues

• Kant’s view: Traditional arguments for God reduce to ontological argument

  • Rational demand for God's existence doesn’t equate to actual existence

• Philosophical consequences

  • From Kant: movement toward irrationalism, existential philosophy, and cultural relativism