Aquinas' Five Ways

Definition

Aquinas' Five Ways are five arguments for the existence of God presented by Thomas Aquinas in his work, 'Summa Theologica'. These arguments are rooted in the cosmological framework, addressing the need for a first cause or necessary being that explains the existence of everything else in the universe. Each way aims to demonstrate that God is the ultimate cause behind the existence of things, moving from observable phenomena to a necessary transcendent being.

5 Must Know Facts For Your Next Test

1. The Five Ways include the Argument from Motion, Argument from Causation, Argument from Contingency, Argument from Perfection, and Argument from Teleology.
2. Aquinas argues that change requires a mover, and since there cannot be an infinite regress of movers, there must be an Unmoved Mover, which is God.
3. In the second way, Aquinas posits that every effect has a cause; if every cause were caused by something else, there would be no first cause, hence the necessity of God as the first cause.
4. The Argument from Contingency states that since many things in existence could not have existed (are contingent), there must be a necessary being that causes their existence.
5. Aquinas concludes that the various degrees of perfection observed in beings lead to the existence of a perfect being, which he identifies as God.

Review Questions

• How do Aquinas' Five Ways function together to argue for the existence of God?
  • Aquinas' Five Ways work collectively by establishing different aspects of causality and necessity to argue for God's existence. Each way targets a different aspect of reality—motion, causation, contingency, perfection, and design—to build a comprehensive case. By showing that each observable phenomenon ultimately points towards an uncaused cause or necessary being, Aquinas reinforces the idea that all paths lead to one conclusion: the existence of God.
• Critically assess how Aquinas’ use of empirical observation in his Five Ways impacts their validity as arguments for God's existence.
  • Aquinas employs empirical observation as a foundation for his Five Ways, grounding his arguments in tangible realities rather than abstract reasoning. This approach lends some degree of credibility as it resonates with human experience. However, critics argue that reliance on observation can limit the arguments’ scope and may not account for phenomena that exist beyond human perception. Additionally, challenges arise regarding whether causality observed in nature can be directly extrapolated to necessitate God's existence.
• Evaluate the implications of Aquinas’ Five Ways on modern philosophical discussions about the existence of God and its relevance today.
  • Aquinas' Five Ways continue to hold significance in contemporary philosophy as they stimulate ongoing debates about metaphysics and the nature of existence. The implications of his arguments invite examination of both classical and modern perspectives on causation and necessity. Modern philosophers may critique or support these ideas through lenses like naturalism or existentialism. Ultimately, Aquinas' framework remains a touchstone for those grappling with questions about divine existence in light of scientific discoveries and philosophical advancements.

Related terms

Cosmological Argument: An argument for the existence of God that asserts that everything that exists has a cause, leading to the conclusion that there must be an uncaused first cause, which is God.

Contingency: The quality of being dependent on something else for existence; Aquinas argues that contingent beings lead to the necessity of a being that exists independently.

Teleological Argument: An argument for God's existence based on the order and purpose observed in the universe, suggesting a designer behind its complexity.