They say it doesn’t matter what you believe. Yet we all make our own moral demands on the public square. Why are we still so passionate about truth? And where shall we find it? The consensus is that science gives us ‘tested truth’, but so does history. Do we ever learn any lessons from history, or are the postmodernists correct to say we make up the past for our own purposes anyway? Does the ‘school of Moses and Christ’ make any difference to the way we think today about what is real?