David Cannadine's impassioned, controversial plea for us to recognise the importance of both equality and history. Great works of history have so often had at their heart a wish to sift people in ways that have been profoundly damaging and provided intellectual justification for terrible political decisions. Again and again, categories have been found - religion, nation, class, gender, race, 'civilization' - that have sought to explain world events by fabricating some malevolent or helpless 'other'. The Undivided Past is an agonised attempt to understand how so much of the writing of history has been driven by a fatal desire to dramatize differences - to create an 'us versus them'. Is is above all an appeal to common humanity.