Aquinas' "Third Way" - Argument for the Existence of God

Summary

In this philosophical discourse, Thomas Aquinas explores the rationale behind the existence of something rather than nothing. He introduces the concept of necessary and contingent truths and objects, using them to argue that not all things can be contingent. Aquinas posits that there must be at least one necessary being, which either derives its necessity from an external source or from within itself. He refutes the possibility of an infinite chain of causes, concluding that a necessary being must exist with its necessity originating from itself, which he equates to God.

Takeaways

• 📚 Thomas Aquinas discusses the question of why something exists rather than nothing in his influential works, 'Summa Theologiae' and 'Summa contra Gentiles'.
• 🔍 Aquinas introduces the concept of necessary truths, which are statements that are true and cannot be false, such as 'all bachelors are unmarried'.
• 🌐 He also explains contingent propositions, which are statements that are true but could possibly be false, like 'the desk is against the wall'.
• 🎯 Aquinas applies the idea of necessity and contingency to objects, stating that an object is contingent if it exists but could potentially not exist.
• 🌌 He argues that all contingent things, at some point, fail to exist, which implies that if everything were contingent, there would be a time when nothing existed.
• 🚫 Aquinas refutes the idea that all things are contingent by stating that if there was ever a time when nothing existed, then nothing would exist now, which contradicts the fact that things do exist.
• 🔑 He concludes that there must be at least one necessary thing that exists and cannot fail to exist, which is either caused by an external source or has its necessity from within itself.
• 🔄 Aquinas rejects the possibility of an infinite chain of causes, arguing that there must be a necessary being that starts the chain and has its necessity from within itself.
• 🌟 He identifies this necessary being as God, which is the ultimate explanation for the existence of everything else, concluding his Third Way argument for the existence of God.

Q & A

What is the main question Thomas Aquinas addresses in the script?

Thomas Aquinas addresses the question of why there is something rather than nothing, and why the universe exists at all.

In which two works of Thomas Aquinas does this argument appear?

The argument appears in Thomas Aquinas' 'Summa Theologiae' and 'Summa contra Gentiles'.

What is the difference between the two works where Aquinas presents this argument?

The 'Summa Theologiae' is written for believers who already believe in God, while 'Summa contra Gentiles' is a philosophical piece written without assuming any prior beliefs.

What is a necessary truth according to the script?

A necessary truth is a proposition that is true and cannot possibly be false, such as 'all bachelors are unmarried'.

What is a contingent proposition?

A contingent proposition is one that is true but could possibly be false, like 'the desk is against the wall' which could be moved.

What does it mean for an object to exist contingently?

An object exists contingently if it exists but could also fail to exist, such as a physical wall that could be destroyed.

Can you give an example of an object that exists necessarily according to the script?

The script suggests that the number seven might be an example of a necessary object, as it seems to exist and could not fail to exist.

What are the two assumptions Aquinas makes before presenting his argument?

The two assumptions are that some things are contingent and that all contingent things fail to exist at some time.

What is the conclusion Aquinas reaches if everything were contingent?

If everything were contingent, there would be a time when nothing existed, which would mean nothing would exist now, contradicting the fact that things do exist.

What does Aquinas argue about the necessity of a being?

Aquinas argues that at least one thing is necessary, meaning it exists and cannot fail to exist. This necessity could either come from an external source or from within itself.

Why does Aquinas reject the possibility of an infinite chain of causes?

Aquinas rejects the possibility of an infinite chain of causes because it would not have a starting point, which is necessary to explain the existence of everything else.

What is the final conclusion of Aquinas' Third Way argument?

The final conclusion is that there is a necessary being that exists and has its necessity from within itself, which Aquinas identifies as God.