This Man Claimed to Prove the Existence of God Nearly a Millennium Ago

Anselm, an eleventh-century philosopher attempted to prove the existence of God

Aarohi Lakhera
4 min readJun 22, 2024

The existence of God has always been a game of wits and battles. Nobody has ever been able to prove God as real or a mere myth with pure surety. Today’s man is occupied with the modern world and seldom gets the time to think over such ravelling topics. However, it is true that a man named Anselm came up with a rather intriguing argument to prove the existence of God nearly a thousand years ago.

Anselm, who became the Archbishop of Canterbury in 1093, is the originator of the Ontological Argument on the Existence of God. This was probably the most highly debated and the most popular argument ever for the existence of God, and is still commonly talked about.


1. It is a conceptual truth (or, so to speak, true by definition) that God is a being than which none greater can be imagined (that is, the greatest possible being that can be imagined).

2. God exists as an idea in the mind.

3. A being that exists as an idea in the mind and in reality is, other things being equal, greater than a being that exists only as an idea in the mind.

4. Thus, if God exists only as an idea in the mind, then we can imagine something that is greater than God (that is, a greatest possible being that does exist).

5. But we cannot imagine something that is greater than God (for it is a contradiction to suppose that we can imagine a being greater than the greatest possible being that can be imagined.)

6. Therefore, God exists.

‘Thus even the fool is convinced that something than which nothing greater can be conceived is in the understanding, since when he hears this, he understands it; and whatever is understood is in the understanding. And certainly that than which a greater cannot be conceived cannot be in the understanding alone. For if it is even in the understanding alone, it can be conceived to exist in reality also, which is greater. Thus if that than which a greater cannot be conceived is in the understanding alone, then that than which a greater cannot be conceived is itself that than which a greater can be conceived. But surely this cannot be. Thus without doubt something than which a greater cannot be conceived exists, both in the understanding and in reality.’


Now, all of this might be a bit too difficult to understand and I am sure you are already scratching your heads. So here’s a simple explanation:

· Anselm starts out by giving a definition of God as that which nothing greater can be conceived (A). He mocks athiests by stating that even the fool would agree that if a God were to exist, he would be the greatest conceivable being.

· He then says that because everyone understands this definition of God, God exists in our understanding.

· He further says that the God that exists in reality must be greater than the God that merely exists in our minds. In simple words, I might have a plan to build an amazing rocket in my mind but if I actually make that rocket- the rocket that exists in reality is obviously greater than which I had conceived.

· Then he supposes that God does not exist in reality, but only in our understanding (S). However, if God were to exist, the God in reality would certainly be greater than the God in understanding.

· But then we could conceive of something greater (God in reality) than the greatest conceivable being (from A). Since that is a contradiction, the supposition (S) must be false.

· Therefore, God exists in understanding and in reality i.e. God exists.

This argument has had many people object to it, the most famous ones being Immanuel Kant, Gaunilo, and Descartes.

The foremost objection to the argument was about the definition of God. Anselm cleverly puts out a definition of God that would suit his argument. He asserts that even an atheist (fool) would agree to it, giving little space for reconsideration. The definition of God is different for everyone but Anselm states it dominantly like a fact.

Gaunilo, who was the first to criticize this argument said that with Anselm’s logic, he could prove the existence of anything. He provides an analogy of a perfect island.

Immanuel said that existing isn’t the quality or essence of a being. What he means is that the qualities of an object constitute things like its color, material, shape, etc. Existing is not a characteristic of an object, nor a quality. Therefore, it is wrong to say that an object in reality is greater than one in understanding simply because it exists.

It is also very notable that Anselm uses complicated texts and convoluted use of phrases, almost like a tongue twister. This is what makes it especially difficult for people to point out the mistakes when they read it for the first time. He also uses phrases like ‘without doubt’ and ‘certainly’ which makes the reader lean deeper into his insight.

Whichever side you may be on, we have to admire the brilliance of Anselm. In times like which he lived in, he certainly put out quite a strong point. And deservedly so, even today philosophers analyze his argument and the objections to it. Anselm might not have proven the existence of God, but he did leave his work for generations to ponder upon.



Aarohi Lakhera

Cultivating mindfulness and high spirits. Writing about mental health and other psychological aspects.