Reviewed by John MorrillAllen Lane, 434pp, £20Tablet bookshop price £18                    Tel 01420 592974This is both a most ambitious and a most bizarre book, full of wisdom and startle and full of holes. Larry Siedentop, a lecturer in politics in Oxford for several decades and the author of a highly regarded study, Democracy in Europe (2001), examines in this new book the source of what makes Europe Europe, of how “the invention of a new, equal, social role, the individual, gradually displaced the claim of family, tribe and caste as the basis of social organisation”. He finds the source of this “moral revolution” in Christianity and specifically in the wri