AFORMER Primate of the Anglican Church in Australia, Keith Rayner, told the National Press Club more than 10 years ago that Christians believe there is a fundamental truth - their mistake is to believe they have it.

The search for that fundamental truth continues - too often acrimoniously and occasionally with some mutual respect.

An example of the latter was The Reason for Faith Festival in Melbourne last week. There was no coincidence it was the week after the Global Atheist Convention, also held in Melbourne.

The festival had 11 events, of which about half included atheists in the discussions.

The evangelical city bible forum, established in all mainland state capitals but not Canberra, is a major partner in the coalition which organised the festival. National director Peter Kaldor says one of the forum's main values is respect. And quite reasonably he says, ''It is very difficult to have a meaningful conversation with anyone unless you show genuine respect.''

He says that in conversations with atheists, the aim is to ask ''the bigger questions''.

He says in the environment of daily work it is very easy to put aside the bigger questions of life, such as the meaning of life and is there a God? Then there is the question of suffering; of separation, divorce and suicide.

Christians are taught there is a loving God. So I ask why a loving God allows or causes suffering.

Kaldor says that is traditionally the hardest question for believers to respond to. Without attempting to answer it he said, ''Absolutely, that is a big question.''

To the forum's credit, it seeks to tease out such questions with atheists and agnostics to broaden the thinking of all. Kaldor recognises the difficulty of having fruitful discussions if the parties are interested only in advancing their particular beliefs.

''If you have very entrenched views, it is sometimes very difficult to be open-minded and to listen carefully to someone else. I think the same is true whether you are a believer or an atheist.''

Though last week's festival in Melbourne seems to have been prompted by an increasing atheistic aggression, Kaldor says, ''I wouldn't say we are limited to reaching atheists. Our organisation primarily is set up to be able to engage with workers who commute to the major business districts of Australia. I guess the fundamental principle we have to share is the idea of God's unconditional love for humanity, expressed through the person of Jesus Christ.''

A major, perhaps the major, criticism of Christianity by prominent atheists is its inability to scientifically prove the existence of its God. Kaldor says there are all sorts of truths, including scientific truths, from which society has benefited.

''The danger, I think, is when that method is extrapolated to the rest of life. All of us know from common experience there are many things in our lives which clearly don't fit that scientific mould.''

For example, he says he cannot prove scientifically his wife loves him. He says that when truth is reduced purely to a scientific truth, the historic basis of Christianity is dismissed too quickly and seen as not a valid form of truth.

''I would want to expand our notions of truth and expand our ideas of evidence.''