Never before had I known the sudden quiver of understanding that travels from word to brain to heart, the way a new language can move, coil, swim into life under the eyes, the almost savage leap of comprehension, the instantaneous, joyful release of meaning, the way the words shed their printed bodies in a flash of heat and light.

The very worst impulses of humankind can survive generations, centuries, even millennia. And the best of our individual efforts can die with us at the end of a single lifetime.

The thing that most haunted me that day, however...was the fact that these things had - apparently - actually occurred...For all his attention to my historical education, my father had neglected to tell me this: history's terrible moments were real. I understand now, decades later, that he could never have told me. Only history itself can convince you of such a truth. And once you've seen that truth - really seen it - you can't look away.

Faith is simply whatever is real to us.

It's funny; in this era of e-mail and voice mail and all those things that even I did not grow up with, a plain old paper letter takes on amazing intimacy.

As a historian, I have learned that, in fact, not everyone who reaches back into history can survive it. And it is not only reaching back that endangers us; sometimes history itself reaches inexorably forward for us with its shadowy claws.

I think it's important to recognise that 'The Da Vinci Code' opened up a vast new audience for a general readership interested in historical detective stories and research into history.