The Fine-Tuning Argument

The Fine-Tuning Argument is a modern version of the teleological argument for the existence of God. It suggests that the fundamental constants and laws of the universe appear to be precisely calibrated to allow for the existence of complex life, and that this fine-tuning is best explained by the existence of an intelligent designer, namely God.

The Argument

The fundamental constants and laws of the universe are finely-tuned for the existence of complex life.
This fine-tuning is either due to physical necessity, chance, or design.
It is not due to physical necessity or chance.
Therefore, it is due to design.
The best explanation for this design is an intelligent creator, i.e., God.

Proponents argue that the probability of a life-permitting universe occurring by chance is astronomically low, making the design hypothesis the most plausible explanation.

The Rebuttals

Multiverses: The idea that our universe is just one of many in a vast multiverse could explain the apparent fine-tuning. In a multiverse with varying physical constants, it's not surprising that we find ourselves in a universe capable of supporting life.
Anthropic Principle: The weak anthropic principle suggests that we shouldn't be surprised to observe a universe capable of supporting life, as we could not exist to observe it otherwise.
Lack of Fine-Tuning: The universe is not as finely-tuned as often claimed. 99% of our universe is not fine-tuned for life.
Problem of Alternative Life: Our understanding of what conditions are necessary for life is based solely on life as we know it. It's possible that other forms of life could exist under very different conditions.
The Fine-Tuner: If complex things requires a designer, a even more complex designer also requires an explanation.