The Fine-tuned Universe Theory, according to Wikipedia is the belief that, "our universe is remarkably well suited for life, to a degree unlikely to happen by mere chance". It is typically used to argue that our universe must therefore be the result of Intelligent Design.

One of the most common counter-arguments to this view based on the Anthropic Principle. The argument is that if the conditions were not such that life would be possible, then we would not be able to observe this, as we would not be alive. Therefore, we shouldn't be surprised that the universe has favourable conditions.

I am going to argue that this particular application of the anthropic principle is in fact an incorrect way to deal with this problem. I'll begin first by explaining one way to deal with this problem; afterwards I will explain why the other way is incorrect.

Two model approach

We begin with two modes:

• Normal universe model: The universe has no bias towards supporting life
• Magic universe model: The universe is 100% biased towards supporting life

Alice notices that Earth survived the cold war. She asks Bob why that is. After all, so much more likely for Earth not to survive. Bob tells her that it's a silly question. The only reason she picked out Earth is that it's her home planet, which is because it survived the cold war. If Earth died and, say, Pandora survived, she (or rather someone else, because it's not going to be the same people) would be asking why Pandora survived the cold war. There's no coincidence.