Q. It is a well-known scientific corollary that absence of proof is not proof of absence. The kinds of models that you describe in your book are really a probabilistic debunking that derive their strengths from 95% confidence intervals and unlikelihood of the hypothesis but not proof that it doesn't exist. Can you shed a bit more light on this?

The word "proof" has at least two different meanings. In logic and mathematics, a proof or disproof is with certainty given the starting assumptions. In science and law, proof means beyond a reasonable doubt. The latter allows one to conclude that
God can be "proved" not to exist if the data show this beyond a reasonable doubt.
Note I use "show" rather than "prove" in the subtitle to avoid that confusion.

Q. One of the arguments that is made by people who believe in God is that there must a reason to our existence. This is sort of an existentialist argument that says that we must have a cause behind our lives and only human lives, I may add. What do you think of this?

That is simply a pious hope. There is no basis, and I would add, no evidence, for this. In fact, the universe looks just as it should be expected to look if there is no special role or purpose for humanity. However, it is important for me to add that this does not mean that we cannot find purpose in our own lives in family, work, art, music, doing good deeds, and so on. In fact, releasing the bonds of religion gives us more freedom to explore all that life has to offer.

Q. Tell us a little more about the kind of problems you see if we allow religious superstition to dictate policy and even science.

As documented in several other books, the religion-based decision making of the
Republicans and Bush administration does more harm than good, threatens the health and well being of all of us, and increases the amount of unnecessary human suffering in the world. For example, most of the federal money spent on AIDS, in Africa and America, goes to advocating abstinence and none to condoms. Scientific studies showing that abstinence does not work are deleted from government reports.

Q. Any final words to the believers and the non-believers?

If scientific evidence were ever found for God or some other form of the supernatural, then scientists like myself would become believers. I give hypothetical examples of observations that would convince me that God exists. I ask all believers and nonbelievers to look at the data and argue about it rationally, without polemics or ad hominems. I try to do this in my book.