Philosophy: Anselm & the Argument for God (Crash Course Philosophy #9)

1. Introduction to Philosophy of Religion vs. Theology

Philosophy of religion is often confused with theology because both study God and religion as their central topics. However, their foundational premises and methodological boundaries are entirely distinct.

• Theology: Starts with the presupposition that God exists and then investigates the implications and consequences of that faith. Theology attempts to resolve internal philosophical problems that arise from religious belief, but the non-existence of God is never placed on the table—atheism is simply not an option.
• Philosophy of Religion: Starts entirely from scratch. Every belief, including sacred and foundational religious convictions, is placed on the discussion table and subjected to rigorous critical scrutiny. Nothing is exempt from examination, and faith alone is insufficient as an intellectual justification.

Note: From a philosophical standpoint, defining faith as "proof against evidence" or something that requires no proof renders it epistemically empty. If someone claims faith that the moon is made of green cheese, it holds no philosophical weight until supported by rational argument.

2. What Philosophy of Religion Is NOT

To isolate the exact scope of philosophical inquiry regarding God, it is vital to eliminate methods that do not constitute valid philosophical proof:

• Upbringing and Cultural Conditioning: Believing something simply because your parents taught it proves nothing about its objective truth. If parental upbringing validated truth, every conflicting religion (and atheism) would simultaneously be true. Upbringing explains why you believe, not whether the belief is objectively true.
• Scriptural Inerrancy: You cannot use text written inside a holy book to prove the historical or metaphysical truth of that book. Doing so is circular reasoning. While textual and historical criticism help us understand when and where scriptures were written, they do not establish divine metaphysical reality.
• Sociology, Anthropology, and Psychology of Religion: These disciplines explain the human, social, and emotional origins of religious beliefs, but they do not answer the foundational philosophical question of whether God actually exists.

3. The Core Mental Model: Anselm and Ontological Arguments

Long ago in the 11th century, the French Benedictine monk Anselm of Canterbury argued that the existence of God can be demonstrated purely a priori (through deductive reasoning based on definitions, without needing empirical observation).

Because the philosophical study of being and existence is called ontology, arguments of this type are known as ontological arguments.

Real-Life Analogy: The Concept of Perfection

Imagine the most magnificent, awe-inspiring, perfect entity you can possibly conceive.

• According to Anselm, whatever you imagine, God is by definition greater still.
• Anselm defined God as "that than which no greater can be conceived."

4. Step-by-Step Evolution of Anselm’s Deductive Proof

Anselm asserted that things can exist in two distinct ways:

1. In the mind alone (imaginary/conceptual existence, like unicorns or Santa Claus).
2. In both the mind and reality (actual existence, like real horses or a slice of pizza).

Anselm made a crucial logical observation: Anything is greater and better if it exists in reality as well as in the mind.

• A fictional unicorn is cool, but a real unicorn would be objectively better.
• Therefore, if we define God as the greatest conceivable being, an entity that exists only in the mind cannot be the greatest, because a matching entity existing in reality would be greater.
• Consequently, to remain the greatest conceivable being ("that than which no greater can be conceived"), God must exist not only in our imagination, but in objective reality as well.

Anselm's Formal Deductive Argument:

5. Guanilo’s Parody Counter-Argument

Anselm was confident he had crafted an infallible proof, but a contemporary French monk named Gaunilo was unconvinced. Gaunilo demonstrated that Anselm's logical structure could be used to prove the necessary existence of literally anything imaginable.

To expose the flaw, Gaunilo constructed a parallel argument to prove the existence of a Lost Island:

• Imagine the most perfect, idyllic tropical island imaginable—complete with endless beaches, perfect weather, and pristine landscapes.
• If this island existed only in our minds, it wouldn't be the greatest island possible; an island that actually exists in reality would be superior.
• Therefore, by Anselm's logic, this perfect lost island must exist in reality, otherwise it wouldn't be the greatest conceivable island.

Gaunilo's critique highlighted that you cannot simply define things into existence using conceptual perfection.

6. Anselm’s Defense and the Fallacy of Begging the Question

Anselm responded to Gaunilo by claiming that his ontological argument only works for necessary beings—entities whose very nature is to exist—which applies exclusively to God, not to contingent things like islands.

However, philosophers point out that Anselm's defense commits a classic logical fallacy: Begging the Question (Petitio Principii).

7. Immanuel Kant’s 18th-Century Critique: Existence is Not a Predicate

Centuries after Anselm, the 18th-century German philosopher Immanuel Kant delivered a fatal blow to the ontological argument.

Kant’s central insight: Existence is not a predicate (or property).

• A predicate is a descriptive property that adds to the concept of a thing (e.g., "red," "triangular," "heavy").
• If you have a concept of a triangle, you can list its predicates: it has three sides and interior angles summing to 180 degrees. If the triangle exists, it still has those exact same three sides; adding "existence" does not add a new property to the concept.
• Kant argued that Anselm’s mistake was treating existence as a perfection or a descriptive attribute that can be added to an object's essence. You can define what an entity's characteristics would be if it exists, but you cannot use existence itself to prove that the entity is real.

8. The Invisible Gardener Parable (John Wisdom)

To illustrate how unfalsifiable religious claims function in philosophical debate, 20th-century British philosopher John Wisdom introduced the parable of the Invisible Gardener.

Thought Bubble: The Parable Walkthrough

This parable highlights the philosophical tension surrounding claims that adjust themselves infinitely to evade empirical disproof.

9. Summary and Key Takeaways

• Philosophy vs. Theology: Theology presupposes God's existence and explores its implications; philosophy of religion starts from scratch, putting every belief, including sacred ones, on the table for critical analysis.
• Rejection of Dogmatic Proofs: Upbringing, scriptural circularity, and sociological or psychological origins do not constitute objective philosophical justifications for religious truth.
• Ontological Arguments: Originating with St. Anselm, these are a priori deductive arguments attempting to prove God's existence based entirely on the definition of God as "that than which no greater can be conceived."
• The Perfection Premise: Anselm argued that because existing in reality is greater than existing merely in the mind, the greatest conceivable being must exist in reality to truly be the greatest.
• Gaunilo’s Island Counter: Gaunilo demonstrated that Anselm's logic is absurd by using the exact same structure to "prove" the necessary real-world existence of a perfect mythical island.
• Begging the Question: Anselm defended his argument by claiming it only applies to "necessary beings," thereby committing the fallacy of assuming the conclusion within the definition.
• Kant's Refutation: Immanuel Kant dismantled the ontological argument by establishing that existence is not a predicate—you cannot define existence into an object's essence.
• Shared Conclusions without Shared Logic: Gaunilo and Kant both believed in God, yet they successfully refuted Anselm's argument, proving that one can reject a flawed logical proof while still holding the conclusion.