The Cosmological Argument Background

Aquinas wasn't just making wild guesses about God's existence. His approach was methodical and evidence-based, following the principle that "one must proportion his belief to his evidence." The word 'cosmological' comes from 'cosmos', referring to our space-time universe.

Unlike other arguments for God's existence, Aquinas used an inductive and a posteriori approach. This means he started with observations of the real world rather than pure logic. He noticed that everything around us seems to depend on something else for its existence.

The heart of his argument rests on rejecting infinite regress - the idea that causes could go back forever without a starting point. Think of dominoes falling: something must have pushed the first one, or the chain never begins.

Key Point: Aquinas believed there must be a necessary being (something that cannot not exist) to explain why contingent things (things that could exist or not exist) are here at all.

The Third Way Explained

Aquinas structured his Third Way as a logical sequence that's surprisingly easy to follow. He starts with a simple observation: everything in the natural world is contingent - it exists, but it doesn't have to exist.

Here's his reasoning: if everything is contingent, then at some point there was nothing at all. But "ex nihilo nihil fit" - out of nothing, nothing comes. Since something clearly exists now, there must be a necessary being that couldn't fail to exist.

Aquinas then tackles an important objection. What if necessary things exist, but they're all caused by other necessary things? His answer: this creates another infinite chain, which explains nothing. There must be an uncaused necessary being at the foundation.

This uncaused necessary being, according to Aquinas, is what we call God. It's the anchor that prevents the whole system from collapsing into meaningless infinite regress.

Think About It: Imagine a bicycle wheel - if you remove the central hub, all the spokes collapse. Aquinas sees God as the essential "hub" of existence.

Major Criticisms of Aquinas

Bertrand Russell delivered some of the strongest criticisms of Aquinas' argument, particularly through his famous debate with F.C. Copleston. Russell's main weapon was the fallacy of composition - just because parts have a quality doesn't mean the whole does.

Russell argued that even if everything in the universe is contingent, the universe itself might not be contingent. It's like saying every human has a mother, therefore the human race has a mother - clearly faulty logic.

David Hume and Kant attacked from a different angle. They insisted that all claims about existence must be synthetic - verifiable through sense experience. Aquinas, they argued, simply assumed God's necessary existence without proper evidence.

William of Ockham's Razor suggests we should favour theories with the fewest assumptions. Why assume God when the universe's existence might simply be a brute fact - something that just is, with no explanation needed?

Russell's Challenge: "The universe is just there, and that's all" - sometimes the simplest explanation is that there isn't one.

The Value and Limitations of Aquinas' Argument

For believers, Aquinas' argument provides enormous value by putting faith into reason. It shows that religious belief doesn't have to abandon logic - instead, it can use philosophical thinking to support theological understanding.

The argument's basic idea remains accessible despite its technical language. Most people can grasp that our contingent universe might need a necessary foundation - it connects with our everyday experience of cause and effect.

However, modern philosophers like R.M. Hare suggest we all operate with 'bliks' - fundamental worldviews that can't be changed by arguments. If this is true, then Aquinas' Christian 'blik' might prevent him from seeing alternatives, just as an atheist's 'blik' prevents them from accepting God.

Gerry J. Hughes offers a more optimistic view, arguing that we should expand our idea of 'proof' beyond pure logic to include probability - much like science does. Perhaps Aquinas doesn't need to provide absolute certainty, just reasonable likelihood.

Food for Thought: Is it better to have a probable explanation (God) or accept that some things (like existence itself) might be permanently unexplainable?