But he could not forget anything, and so those lists sat in his mind, cluttering it; and he could not form abstractions from the groups of objects: everything was discrete, separate. "By the end of his life, all he could do was travel from town to town demonstrating his peculiar talent for memorising lists of words," writes Kotre.So we have to forget some things, to be able to remember others. He cites the case of a young Russian newspaper reporter called Shereshevskii, who could retain lists of words, and recall them perfectly forwards and backwards, for years. Others contend that we remember everything perfectly: it's all "in there", and the only problem is getting it out.

This camp tends to contain strong believers in the idea of "recovered memories", where adults' repressed recollections of horrific events in childhood can be pulled back to the surface intact. But as John Kotre points out, in this beautifully guided tour through the landscape of our minds, we all forget We have to: a perfect memory would be a curse. Did Michael Portillo's or John Major's office "forget" the anniversary of the Somme? Are people who say they were sexually abused as children remembering real events, or misinterpreting others? Are eyewitnesses who give different descriptions of the same event lying? If we were all blessed with perfect memories, some say, we could know for sure. But if Labour fails to deliver on its agenda it will mean the ideas that will have triumphed in welfare state reform will be those of the right - which would almost certainly mean more steps down the road that Clinton has now agreed to tread.Blair will either be left running broadly with the tide that Peter Lilley has set flowing - a cut and squeeze approach to social security spending; or, worse from his point of view, he might find himself faced by a populist Tory party led by a Portillo or a Redwood advocating yet more of the Republican agenda. Faced with that and no deliverable alternative of his own, Blair could find himself, Clinton-like, having to adopt more of these new Conservatives' clothes He might have to And after all, he's done it before..