It’s Apologetics Time :-). Today, we tackle one of those arguments for God’s existence that (most of the time) evokes indifference, confusion, or controversy. Occasionally, it may get a nod of approval – but not often. But this argument for the existence of God is one of the most intriguing ways to think about the subject.
So, today, we tackle the question: What if God must exist?
This article is part of an ongoing, off-and-on series exploring various reasons to believe in God. We’ve looked at beauty. Now, we turn to a more abstract—but fascinating—line of reasoning: the ontological argument.
What Is the Ontological Argument?
The ontological argument is a philosophical case for God that starts with the very idea of God. It was formally introduced by Anselm of Canterbury in the 11th century AD (or, for the politically correct who like to change language to be more inclusive, CE), and it has been debated ever since.
Here’s the basic idea:
- God is, by definition, the greatest possible being.
- A being that exists both in the mind and in reality is greater than one that exists only in the mind.
- Therefore, if God exists in the mind, He must also exist in reality.
If that makes your head spin, you’re not alone. But many brilliant thinkers have taken this argument seriously, including René Descartes, Alvin Plantinga, and even critics like Immanuel Kant.
For the 10-Year-Old in All of Us
Let’s simplify it:
Imagine the most powerful, wise, loving, amazing being you can think of. Now, imagine that this being only exists in your imagination. Not as impressive, right?
But what if that being existed for real? That would be even better.
The argument says: If God is truly the greatest being imaginable, then He can’t just be imaginary. He has to exist in real life, or else He wouldn’t be the greatest.
Boom. That’s the ontological argument.
Common Objections to the Ontological Argument
Skeptics have challenged the argument for centuries. Here are some of the most common objections:
- You can’t define things into existence. Just because you define God as the greatest possible being doesn’t mean He actually exists.
- The logic seems circular. The argument appears to assume what it’s trying to prove.
- You could apply this to anything. Why not define a perfect island into existence?
- It’s too abstract. The argument is too far removed from real-world experience to be persuasive.
How Supporters Respond
Supporters of the ontological argument don’t say it’s the only proof of God—but they do believe it’s a powerful logical insight. Here’s how they respond:
- Defining God Isn’t Arbitrary. Unlike a “perfect island,” the idea of a greatest possible being isn’t random. God is defined as a necessary being—meaning He exists in all possible realities, not just one.
- It’s Not Just Wordplay. Philosophers like Alvin Plantinga have reformulated the argument using modal logic (logic about what’s possible or necessary). Plantinga’s version argues:
- If it is possible that a maximally great being exists, then that being exists in some possible world.
- If that being exists in some possible world and is maximally great, it must exist in all possible worlds.
- That includes our world. So God exists.
- Circular Reasoning Isn’t Required. The argument begins with a reasonable definition, not a presupposition that God exists.
- It Shows Coherence. Even if you don’t find it fully persuasive, the ontological argument is important because it shows that belief in God is logically coherent—and in some formulations, even necessary.
Why It Matters
To be honest, I’m not a big fan of the ontological argument (though I do find Plantinga’s reformulation intriguing). I rarely use it. You might not either. And that’s okay. But it reveals something profound:
We’re not just guessing about God. We’re reasoning.
Faith is not blind. Faith can think.
Thank you for Reading!
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