Unit AS 8: An Introduction to the Philosophy of Religion
Chapter: Arguments for the Existence of God
Welcome to your study notes for Arguments for the Existence of God! Whether you are aiming for top marks or looking to build your confidence, these notes break down every key thinker, argument, and counter-argument step by step.
Philosophers generally divide arguments for God's existence into two main categories based on how they gather evidence:
• A Posteriori Arguments: Arguments based on experience and observation of the world around us. (Examples: The Cosmological and Teleological arguments).
• A Priori Arguments: Arguments based on reason and definitions alone, without relying on sensory observation. (Example: The Ontological argument).
Memory Tip: Think of A Posteriori as coming post (after) experience, while A Priori comes prior (before) experience!
---1. The Cosmological Argument
The Cosmological Argument is an a posteriori argument. It starts from a simple observation: the universe exists, so what caused it to be here?
Thomas Aquinas: The Three Ways
In his famous work, Summa Theologica, St. Thomas Aquinas offered five ways to prove God's existence. The first three make up the classical Cosmological Argument:
1. The First Way: Motion (Change)
• Everything in the world is in a state of motion or change (moving from potential to actual).
• Whatever moves must be moved by something else.
• This chain of movement cannot go back forever into the past (no infinite regress).
• Therefore, there must be a primary cause of motion that is not moved by anything else: an Unmoved Mover, which everyone understands to be God.
2. The Second Way: Causality (Cause and Effect)
• In the world, we observe a chain of causes and effects.
• Nothing can be the cause of itself (because it would have had to exist before itself, which is impossible).
• You cannot have an infinite regress of causes, or there would be no start to the chain and therefore no present effects.
• Therefore, there must be a first, uncaused cause: an Uncaused Cause, which is God.
3. The Third Way: Contingency and Necessity
• Everything in the physical universe is contingent (it can exist or not exist; it comes into being, lasts for a time, and perishes).
• If everything were contingent, at one time there would have been absolute nothingness.
• If there was ever nothing, nothing could have ever started (from nothing, nothing comes).
• Therefore, there must exist a Necessary Being (a being that cannot not exist and depends on nothing else for its existence), which we call God.
Modern Variant: The Kalam Cosmological Argument
Championed in modern philosophy by William Lane Craig, this argument focuses on the idea of time and origins:
• Whatever begins to exist has a cause.
• The universe began to exist (an actual infinite past is impossible; history cannot be endless).
• Therefore, the universe must have a cause, which Craig identifies as a personal creator.
Challenges to the Cosmological Argument
1. David Hume
• The Fallacy of Composition / Leaping to Conclusions: Hume argued that just because individual events within the universe have causes, it does not mean the entire universe itself has a single cause. Why assume the whole has the same properties as its parts?
• Hume also questioned why the first cause must be the traditional Christian God rather than an unknown natural force or multiple causes.
2. Bertrand Russell
• Russell rejected the search for an ultimate cause, famously stating that the universe is just a "brute fact".
• In a famous debate, Russell stated: "I should say that the universe is just there, and that's all." Asking for a cause of the entire universe is asking a question that has no meaning.
Key Takeaway: The Cosmological argument argues backwards from the existence of the cosmos to an ultimate First Mover, First Cause, and Necessary Being (Aquinas), but critics like Hume and Russell argue that assuming the universe requires an external explanation is an unjustified leap.
---2. The Teleological (Design) Argument
The Teleological Argument (from the Greek telos, meaning 'end' or 'purpose') is also an a posteriori argument. It claims that the order, regularity, and complexity in the natural world point to an intelligent designer.
William Paley: The Watchmaker Analogy
In his book Natural Theology, William Paley presented one of the most famous analogies in philosophy:
• Imagine walking across a heath and striking your foot against a stone. You might casually assume the stone had lain there forever.
• But if you find a watch on the ground, you notice its intricate complexity, delicate cogs, and precise purpose (to tell the time).
• You would naturally conclude that the watch must have had a maker—a Watchmaker who designed it with purpose.
• Paley argues that the natural world contains far greater complexity and purpose than a watch (e.g., the intricate mechanics of the human eye).
• Therefore, the universe must have an intelligent designer, who is God.
Alternative Forms: F.R. Tennant
1. The Anthropic Principle:
Tennant argued that the universe appears specifically fine-tuned to allow intelligent human life to develop. The precise physical conditions required for life suggest deliberate design rather than blind chance.
2. The Aesthetic Argument:
Tennant observed that humans appreciate beauty, art, and music. Because appreciating beauty has no direct survival value in evolutionary terms, Tennant argued it is a sign of a loving, benevolent designer who created a world for human enjoyment.
Challenges to the Teleological Argument
1. David Hume
• Flawed Analogy: The universe is not like a machine; it is organic, ever-changing, and more like a vegetable or living organism than a mechanical watch.
• The "Apprentice God" / Polytheism: Even if there is design, why assume one all-powerful God? It could be the work of a team of gods, or an incompetent "infant deity" or "apprentice god" who made a flawed world and abandoned it.
• Flaws in the World: Natural evil (earthquakes, disease) points to a flawed design or an indifferent designer.
2. Charles Darwin
• Darwin’s theory of evolution by natural selection showed that complex biological features (like the human eye) develop naturally over millions of years without needing a divine designer.
• Apparent design is simply the result of organisms adapting to survive in their environment.
Key Takeaway: Paley uses the Watchmaker analogy to argue that complexity equals design, supported by Tennant's focus on fine-tuning and beauty. However, Hume's philosophical critiques and Darwin's evolutionary theory offer powerful alternative explanations for natural complexity.
---3. The Ontological Argument
The Ontological Argument is uniquely a priori and deductive. It does not look at evidence in the world. Instead, it attempts to prove God’s existence purely by analyzing the definition and concept of God.
St. Anselm of Canterbury (Proslogion)
St. Anselm formulated the argument as a prayer in his work Proslogion:
• Step 1 (The Definition): God is defined as "that than which nothing greater can be conceived" (the greatest possible being).
• Step 2: Even the "fool" who denies God understands this definition in their mind.
• Step 3: It is greater to exist both in reality (in re) and in the mind (in intellectu) than to exist in the mind alone.
• Step 4: If God existed only in the mind, we could conceive of a greater being—one that exists in reality too.
• Conclusion: Therefore, to remain the greatest conceivable being, God must exist in reality.
Challenges to the Ontological Argument
1. Gaunilo of Marmoutiers: The "Perfect Island"
• Gaunilo was a contemporary monk who argued that Anselm's logic was flawed.
• He used a parody: Imagine the "most perfect island" that can be conceived.
• By Anselm’s logic, because it is greater to exist in reality than just in the mind, this perfect island must exist in reality.
• Since we cannot define a perfect island into existence, Gaunilo argued you cannot define God into existence either.
2. Immanuel Kant: Existence is Not a Predicate
• A predicate is a property or characteristic that adds descriptive information to a concept (e.g., "the apple is red and sweet").
• Kant argued that existence is not a predicate. Saying something "exists" does not add any new descriptive quality to the idea of it; it merely states that the concept has an instance in the real world.
• For example, thinking of 100 possible gold coins (thalers) has the exact same characteristics as 100 real gold coins; saying they "exist" adds no new quality to the coins themselves. Therefore, you cannot define existence into the concept of God.
Key Takeaway: Anselm argues that by definition, the greatest conceivable being must possess real existence. Gaunilo and Kant counter that definitions belong to the mind, and you cannot define something into real-world existence.
---4. Pitfall Warnings & Exam Success Strategies
Common Pitfalls to Avoid
• Confusing A Priori and A Posteriori: Never mix these up! Cosmological and Teleological = a posteriori (evidence-based). Ontological = a priori (definition-based).
• Misunderstanding "Contingency": In philosophy, contingent does not mean accidental. It means something that relies on something else to exist and could cease to exist.
• Over-relying on Darwin for Design Critiques: Do not just write about biology! CCEA examiners want to see David Hume's philosophical critiques of Paley (e.g., the machine comparison, apprentice god, team of gods).
• Falling into the "God of the Gaps" Trap: Avoid simply arguing "science cannot explain it, so God must have done it." Analyze whether philosophical arguments provide logical proof or reasonable probability.
Mastering AO2 (Evaluation and Analysis)
In your CCEA AS 8 examination, top marks require a reasoned judgment:
• Do not merely list arguments and counter-arguments side by side.
• Weigh the arguments: Which side is stronger and why?
• For instance, assess whether Paley’s analogy survives Hume's criticisms, or whether Kant successfully demolishes Anselm's logical foundation.
• Conclude clearly on whether these arguments succeed as definitive proofs or whether they serve to support faith rather than prove it.