A popular way in which atheists try to explain religious belief is to label it a "meme". The idea, advanced by evolutionary scientist Richard Dawkins, is that memes are units for transmitting cultural behaviour or beliefs, and they spread or "self-replicate" through the population in a manner analogous to genes in biology.

The theory has its critics in both science and philosophy, and among the unimpressed is the American academic and author Gary Gutting. In his latest book, Talking God: Philosophers on Belief (W.W. Norton & Co.), he quotes the atheist thinker Louise Antony when she says: "It's presumptuous to tell someone else why she believes what she believes – if you want to know, start by asking her."

Gutting, who is based at University of Notre Dame, interviewed a dozen philosophers – some religious and some atheist – for the book to explore the boundaries of reasonable belief. He describes himself as an agnostic Catholic (more of that in a moment!) but doesn’t claim to have a monopoly on wisdom.

Atheists have some strong arguments, he says, but “the weakest intellectual aspect of current atheism is its naive enchantment with pseudoscientific biological and psychological explanations of why people believe”.

When you wrote this concluding comment in the book about 'pseudoscientific' explanations for religion, had you Dawkins's concept of the meme in mind?

“I was thinking of Dawkins but also of many other efforts to use science to explain religion away.

“There are two problems here. First, the explanations are not detailed causal accounts of how people actually come to believe. They’re merely hand-waving sketches of how belief might arise: for example, fear of death, social survival-value of shared myths. There’s no reason to think that, say, the well-educated and reflective believers, of whom there are many, are driven by such simple causes.

“Second, even if we do accept these simple universal explanations of religion, similar explanations will just as well apply to agnostic and atheistic beliefs. Denials of the supernatural might arise from fear of what would happen to me if there were an afterlife. Or they might, as seems to have been the case with Jean-Paul Sartre, originate from a deep-seated refusal of a God who would limit my freedom.”

You characterise agnosticism as a sort of honourable middle ground. But how would you respond to the argument that to be agnostic you must accept there is a realistic chance of there being a God, and that most agnostics merely accept a very slight or wholly theoretical chance?

"I agree that there are agnostics whose doubt is the practical equivalent of atheism-like doubting the existence of extraterrestrials that look like chartreuse squirrels. My agnosticism takes the possibility of God seriously; it's what William James called a 'live option', something that I can plausibly see myself as believing.

“For me, the overall weakness of arguments for atheism helps makes theism a live option. In fact, I’ve found that in an undergraduate class a careful reading of Dawkins’s arguments against God’s existence generally does more to move students away from atheism than does a careful reading of Aquinas’s proofs for God’s existence.”

What’s the best argument for belief in God, in your view?

“For most believers, I think it’s some form of an argument from personal experience. Many people have strongly sensed the presence of an extraordinarily good and powerful invisible person who cares about them. Of course, merely having a strong sense that something’s there doesn’t of itself give a good reason to think that it is there.

“The fact that my son is sure that there’s a monster under his bed doesn’t provide a good reason for thinking that the monster exists.

“The reliability of an experience also depends on how well it fits in with other experiences that I and others have and with my overall worldview. But many people, of diverse times and places, have had repeated experiences of a divine presence. And-for those with worldviews not limited by the dogma of scientific materialism-such experiences may be rightly seen as real possibilities.

“Religious experiences cannot have the decisive force of our encounters with the material world, but I may well be rational in seeing them as support for the existence of God. This can be so even if the argument is not strong enough to rationally compel belief in God.

“Similarly, two astrophysicists who disagree about the likelihood of intelligent life on other planets may both be rational in holding their opposing views. So religious experiences could make theism rational for a believer, even if they don’t make someone else’s atheism or agnosticism irrational.”

You describe yourself as both agnostic and Catholic. How does that work?

“I see religious commitment as having three elements. First, there is a commitment to a religious way of life – engaging in rituals, reading the holy books, following moral rules – as a good way for me to live.

“I think that for many believers, this is the main – or even only – basis of their faith. They have a practical commitment to their religion but not necessarily any views about its intellectual significance. But many believers also have a commitment to their religion as a valuable way of understanding the world and their place in it.

“Here I distinguish understanding from knowledge, since quite different, even incompatible, views may be good ways of understanding the world. So, for example, the views of human existence we find in Jane Austen and in Samuel Beckett could hardly both be literally true pictures of our lives; but each offers a fruitful framework for understanding what it means to be human.

“The third element, knowledge, requires accepting the literal truth of doctrinal claims. This would include the doctrine of the ‘real presence’, as well as other central teachings, such as that God is triune, that Jesus was born of a virgin and rose from the dead, that we will all rise again and live forever in heaven or in hell.

“I’m open to the idea that such extraordinary claims may be literally true, but accepting them would require far more justification than we have available.

“Here it may seem that I’m ignoring the key distinction between knowledge and faith. But on any sensible view faith means belief on the word of someone else - e.g. the Pope, the bishops - as opposed to knowing from your own experience or reasoning. Faith is crucial in human life-almost everything we believe about science and history, for example, is based on what others have told us is true.

“But believing on faith makes sense only if we know that our faith is based on reliable sources. It would be the height of foolishness to believe what the Pope and bishops tell us unless we knew that they were trustworthy witnesses. Nor would it make sense to say that we know the Pope and bishops are reliable just because they themselves say they are. We need independent reasons for thinking that we can trust them.

“Traditional apologetics has tried to provide such reasons by complex historical arguments, but the arguments are not convincing and few believers pay any attention to them.

“My conclusion is that we should treat the church’s doctrines as doubtful if they are meant to be literal truths about what is, was, or will be. They remain, however, valuable as stories or ways of thinking that enhance our understanding of human existence. That’s the residue of agnosticism in my Catholicism.”

ASK A SAGE

Question: If you don't like theism, atheism or agnosticism, is there something else you can believe in ?

George Carlin replies: "Frisbeetarianism . . . the philosophy that when you die, your soul goes up on a roof and gets stuck there."