Melbourne is gearing up to host the Global Atheist Convention, where for three days a coterie of the faithless will urge each other on in their collective scepticism. The most famous proponents of a godless universe will be there - Richard Dawkins, Sam Harris and Daniel Dennett - but this time, sadly, the most engaging and entertaining of them, Christopher Hitchens, won't.

The convention seeks to ''Celebrate Reason'', which seems, well, reasonable enough. We all need something substantial on which to make our judgments, and according to those attending, it's the clear thinkers, those unencumbered by superstition and religious nonsense, who are most likely to arrive at the truth.

2002 Nobel Economics Laureate Daniel Kahneman "draws upon a lifetime of studying human behaviour that has shown him just how unreliable the human mind really is". Credit:Reuters

But while it's easy to mock those with religious beliefs, the atheist appeal to a thoroughly rational, objective position is not without its problems.

Daniel Kahneman, arguably the most influential psychologist alive today, is a Nobel prize winner in economics. He's also the author of Thinking, Fast and Slow, where he draws upon a lifetime of studying human behaviour that has shown him just how unreliable the human mind really is.