A palimpsest is a parchment upon which writing superimposes partly effaced writing, work that bears a soupçon of its earlier form. When the American novelist Gore Vidal titled his memoir Palimpsest he was saying that what he had written had traces of the life that was his subject. Vidal, whose novels include The City and the Pillarand Washington D.C., had this to say about the difference between memoir and autobiography: "A memoir is how one remembers one's own life, while an autobiography is history, requiring research, dates, facts double-checked."
Whether it is an apologia in the manner of John Henry Newman, an Augustinian confession, an autobiography or memoir, life writing is both assessment and reassessment: the author's assessment and our, the readers', reassessment.
The publication of George W Bush's Decision Points this week is the 43rd US president's chance to assess key moments in his personal and public lives, to justify what he feels needs justifying, to attempt to right some matters of historical record, to acknowledge failings, to rescue himself from the dustbin of history and rebuild his reputation.
If anything, Decision Points shows that 14 is about as many major decisions as anyone should have to make in a lifetime.
Bush's biography can be nutshelled in a variety of ways, depending on one's political persuasion. The straight-up, no-agenda version goes something like this: born July 4, 1946 in Connecticut, to George H W and Barbara Bush; paternal grandfather, Prescott, a US senator. Grew up in Texas. Phillips Academy boarding school, then Yale University (BA, history, 1968). Fighter pilot in the Texas Air National Guard, missed eight months of service in the early 1970s. Harvard University (MBA, 1975).
Started his own oil and petrol firm in Midland, Texas, where he married a librarian and Dostoevsky-lover, Laura Welch. Lost a bid for Congress in 1978. Raised cash for his father's presidential campaign, introducing himself to major political players and donors, the base he used for his own political runs years later.
In 1986, Bush came to realise "alcohol was beginning to crowd out my energies and could crowd, eventually, my affections for other people". This followed a spiritual awakening and his rebirth as a Christian.
Purchased a minority share in the Texas Rangers baseball team, got a good deal of media exposure, also vital for his later political ambitions. Sold his share for $15 million.
Became governor of Texas in 1994 and set about reforming the state's education system in a manner that had parallels to his No Child Left Behind programme as president: increased state spending and tied teacher promotions to student testing. Simultaneously increased the number of crimes juveniles could be tried for and lowered the age to 14 at which a child could be tried in adult court. Re-elected in 1998 with 70 per cent of the vote. Eight months later, announced his intention to run for the Republican nomination for US president.
Bush's political biography at this point is so recent as to almost not bear repeating, but repeat it we must if only because it points to the difference between autobiography and memoir, what we know and wish to know about a man versus what the man chooses to highlight. In any writing, what is illuminated says something about what is left in shadow.
The controversial win of the presidency, September 11, the attack on Afghanistan, the invasion of Iraq and ouster of Saddam Hussein, Hurricane Katrina: as would be expected, these feature among the decisions Bush chose to highlight in his memoir. So do his alcoholism, his faith and - Africa. Bush increased aid to the continent to $4 billion yearly from $1.4bn and in 2006 vowed that the amount would grow to $10bn by 2010.
From the memoir, we now know Bush believed waterboarding three detainees in Guantanamo Bay was justified because it led to intelligence breakthroughs that prevented attacks (he says he opted against two other "interviewing" techniques because they went too far; he does not name them); he felt "sick" when it turned out Saddam Hussein did not have weapons of mass destruction; that the Israel target in its 2007 air strike on Syria was indeed a nuclear reactor; that he ordered, then rejected, a military strike against Iran because of its nuclear programme; that he almost dropped his vice president, Dick Cheney, from the ticket in 2004, and that he had not planned to host a meeting on the economy in 2008 until after John McCain, the Republican nominee for president, said he was attending such a meeting at the White House.
Of Katrina, he says the most painful moment of his presidency was when the rap artist Kanye West described Bush as racist, "not caring about black people", in his dealing with the post-hurricane flooding.
What do these revelations say about George W Bush? Well, the admission he didn't see the financial meltdown coming and that he was surprised Saddam possessed no WMDs are revelatory. How does the leader of the free world, with all the advisers and intelligence reports he has at hand, not know his justification for war on a sovereign nation is based on a lie, or that the US economy is about to hit the canvas? The admissions recall claims that Bush and his team had been warned, while he was on vacation in August 2001, that a terrorist attack was imminent. His response: back to the wood chopping.
Bush was also slow off the mark regarding Katrina. When he finally visited, he did so from Air Force One. "I shouldn't have flown over and looked," he now admits.
"I made a mistake. I should have landed. I didn't realise a picture of me looking out would look like I didn't give a darn," he told Oprah Winfrey this week while on a media-circus promotional tour.
In the book, he defends himself against charges that he failed to empathise: "This was a problem of perception, not reality. My heart broke at the sight of helpless people trapped on their rooftops waiting to be rescued."
And perhaps his heart did break. He might be evil personified to some, but he's not heartless. Plenty of people have, over the years, characterised Bush as shallow and not especially inward-looking. That might be true but for one major point. Looking at life from the bottom of a bottle and giving control of that life to a higher power require introspection. To admit to alcoholism is to have looked inside, deep.
In an era when personal responsibility is a commodity rarer than indium, where no one accepts blame for anything - from their own smoking-caused cancer to the overeating that led to obesity - Bush's choice to title his book Decision Points emphasises his being the "decider". (Bush famously said in April 2006: "I'm the decider, and I decide what is best. And what's best is for Don Rumsfeld to remain as the secretary of defence." In Decision Points, Bush admits that he sought to make changes at the Pentagon, but couldn't find anyone to replace Rumsfeld.)
Yet, although he made the decisions, he does not accept responsibility for them, if such a distinction can be made. The glass at the bottom of the bottle was thick.
While on NBC this week, Bush was asked whether he considered apologising for his mistakes. He said no. "Apologising would basically say the decision was the wrong decision."
A mistake is one thing. A wrong decision is another. The Bush palimpsest means to efface the wrong decision with the admission of the mistake.
In Vidal's differentiation between autobiography and memoir, the latter is where one harvests lessons from one aspect of one's life. Bush, in admitting mistakes but refusing to apologise for them, moves his book off the shelf of memoir and onto that of apologia. Never mind the fact-checking required for an autobiography.
Presently, there is an online movement encouraging people to visit their local bookstore and move copies of Decision Points from the biography section to the crimes section. Does Decision Points deserve this? Perhaps, perhaps not. The man has his right to expression. It was guaranteed in the constitution he swore an oath to uphold.
The subversion might be moot anyway. On the first day of its publication, Decision Points sold 220,000 copies. A total of 1.5 million were printed. If the track record of presidential memoirs is anything to go by, it will sell well but won't be read. Leslie Gelb, president emeritus of the Council of Foreign Relations, told Reuters this week: Americans will read the book for the "good gossip".
If there is any gossip, that would place the book among tell-alls. It would be a welcome, but a completely uncharacteristic departure if indeed he did tell all. We might wait a while for that version.
GEORGE BUSH: The biog
Born: July 6, 1946, New Haven Connecticut
Education: Yale University, BA, history, 1968; Harvard University, MBA, 1975
Career highlights: Managing partner of Texas Rangers baseball team, governor of Texas, 43rd US president
Personal: Became a born-again Christian and gave up alcohol
Books: A Charge to Keep (1999 campaign books), Decision Points (2010 post-presidency memoir)
Life lessons: His mother, Barbara, once showed him a jar that contained a foetus she had miscarried. He says the event solidified his anti-abortion stance