Memories are made of this

Examples of folly--- struggling on when any rational hope of success has gone---are, to borrow a splendid word from the Bible, legion. Barbara Tuchman wrote a book about them, called The March of Folly: from Troy to Vietnam. Her book was written in 1984, towards the end of a brilliant life. The March of Folly has all Tuchman's trademark clarity, attention-retaining personal details, and her characteristic sweeping overview, but it has something missing. When I first read it nearly twenty years ago, it felt flabby, especially in comparison the astringency of her other books, such as The Zimmerman Telegram. Thinking about it now, I realize that she needed less history and more psychological insight into why people, and not just world leaders, act as they do when confronted with their own personal Trojan Horse.

So, why do people persist in follies, when the mistake is as plain as a pikestaff to everyone except them? In a new book, Mistakes Were Made (But Not by Me): Why We Justify Foolish Beliefs, Bad Decisions, and Hurtful Acts, two psychologists explain that it's basically down to cognitive dissonance (surely one of the most enduring theories in a discipline not noted retaining theories for very long). We form an image of ourselves and believe that image to be 'true', in the sense that there is no dissonance between our actions and the self-image who performed those actions. Confessing a mistake is difficult because it means that our self-image has cracked, perhaps why America treated its Vietnam veterans so badly: they are living reminders of a mistake.

If we grant that we subconsciously exclude the possibility of a mistake from our current thinking about ourselves, can we extend the concept back in time? Humans are notoriously selective about which memories are kept and which are thrown out, or hidden, and this is perhaps why. We retain memories which reinforce our self-image as a caring and thoughtful mother, or whatever structure on which we have built our idea of ourselves. Memories which create dissonance are suppressed. The desire to retain certain memories is manifest in the desire to retain certain objects which have the power to trigger the warming flow of a pleasant memory. I was thinking about this when my sister Mary reminded me about a family photograph I'd forgotten about. Just the thought of the photograph was enough to allow me to relive a delightful day.

In a new book, Memory: An Anthology, Harriet Harvey Wood and A.S. Byatt present the study of memory from two vantages: literature and science. I found the discussion of public memory fascinating, especially Sudhir Hazareesingh's exploration of French public memory. How could a nation which tore itself apart over the Dreyfus affair have allowed the camp at Drancy and the deportation to death of so many of its citizens? These memories, dissonant with the French self-image of themselves as world-leaders in enlightenment and civilisation, have only recently allowed back into the national history.

Space in the brain is limited, and we can't remember everything, so we toss out memories which are unlikely to be needed in the future. This has an evolutionary origin, not hard to see. Why remember places where you failed to catch your dinner? Instead, remember the place and the circumstances under which you did catch your dinner, and the people you ate it with. Perhaps this is why many of our warmest memories are those in which food is shared. The pleasant memories link us back through the generations to those early hunters and their pleasure in knowing that they had succeeded in feeding their family.