In this paper, considering the fact that the universe is fine-tuned for the presence of life, Robin Collins argues that using the "Prime Principle of Confirmation", a design hypothesis should be preferred to the atheistic single-universe hypothesis. That is, it is more reasonable to believe that the universe was designed than that it is not designed.
The argument is as follows:
Premise 1: The existence of fine-tuning is not improbable under theism.Dissent from this conclusion requires either dissent from the premises (which he justifies in the paper) or dissent from the prime principle of confirmation (which has proved a reliable guide in most other contexts).
Premise 2: The existence of fine-tuning is very improbable under the atheistic single-universe hypothesis.
Conclusion: (From 1, 2 and the prime principle of confirmation) Fine-tuning data provides strong evidence in favour of the design hypothesis over the atheistic single universe hypothesis.
He also argues that atheistic many-universe hypotheses - that is, invoking a multiverse - do not provide an explanation of the nature of reality that necessarily avoids the issue of fine tuning and design. The required properties of a multiverse are themselves highly specific.
It goes without saying that the paper, brief as it is, is philosophically more credible and better referenced than "The God Delusion".