From the ancient Greek historian Thucydides to Bristol Palin and Levi Johnston, Petri says political memoirs are rife with fibs, misstatements and selective memory. She talks with NPR's Neal Conan about political biographies, and why she says there's no such thing as "exact memories."
On the importance of a good story, and the "truth truth"
"Pretty much every politician who's risen up lately, from Barack Obama to John Edwards ... they have a story that viewers and readers connect with.
"But the trouble is that the more exciting and more sort of connective your story is, the more likely it is to contain a little bit of what Tim O'Brien memorably called 'story truth' rather than truth truth. He was the guy who wrote The Things They Carried, and he has this great saying that a thing may happen and be a total lie; another thing may not happen and be truer than the truth.
"And that should sort of be the front page of all political autobiographies and all speeches, because what you're getting at is the truth truth."
On whether biographical flubs matter
"No. You can always fix it in post, as they say in the media biz. But as long as you tell a compelling story that gets people to visit it, then later somebody could go in and fact-check it.
"But the worst thing you could do is be boring, I mean, or self-deprecating ... One of my favorite sort of memoir stories that actually turns out to be true is George W. Bush's autobiography. He has this story [of] how his mother gave him a thesaurus, and he's sitting there at school, and he wants to come up with a more elevated word for tears. So he writes this essay where he says, 'lacerates pour down my cheeks.'
"And nobody has ever questioned that because they think, 'Yeah, it sounds about right.' "
On why we get our own stories wrong
"I think part of it is that your memory can only hold so much. You develop this sort of narrative through-line that may be somewhat accurate but is at least colorful. And you value consistency over the actual sort of specifics of things.
"The better a story it is to tell, the less you remember who you've told it to, and also, the easier it is to sort of [wedge] it into the same shape the next time around rather than going back and saying, 'Well, was he really sitting on my left? What was really going on?' It takes on a life of its own when you tell a story enough times, and I think political stories as the sort of ultimate example of the story that gets told and retold over and over again — once you've told it often enough, it becomes true in a way that has no relevance to the initial facts that shaped it."