In the course of the 1830s, a Persian prince visited Europe and was shown all the technological marvels of contemporary Western civilisation. He was duly impressed, but in summing up his impressions he remarked that although God, in his infinite wisdom, had seen fit to grant to the infidel the good things of this world there could be no doubt that Muslims would have the best of it in the next world. For that observer, as for very many other Muslims, the title of this book would be quite meaningless. Nothing, they would argue, has gone wrong. Islam means submission to God’s will; it is the duty of the Muslim to try to live according to God’s law, the sharia; and for the rest, in the familiar concluding words of many a fatwa, God knows best.

Professor Lewis wishes to contrast the wealth, power and splendour of classical Islamic civilisation (during the period, say, from the seventh to the seventeenth centuries of the Christian era) — which, he argues, was (with China) one of the two great civilisations of the world — with Islam’s subsequent relative decline (relative, that is, to the rise of the Christian West). In fact, the question posed by his striking title turns out to be two questions: what went wrong with classical Islamic civilisation, and what went wrong with the attempts of the Muslim world to modernise itself in response to the challenge of the West? Classical Islam, he contends, was the greatest military and economic power of its time and had advanced furthest in what one might call the arts of civilisation. Lewis especially associates Islam with the Middle East, and he sees the height of Muslim power and civilisation embodied particularly in the great Ottoman Empire, which extended from Hungary to the Indian Ocean and from the Barbary Coast to the borders of Iran. Readers may wish to ponder the significance of the facts that far more Muslims live outside the Middle East than within that region, that in the period of what Lewis would regard as Muslim decline Islam was expanding in South East Asia and in Africa, and that it is still probably the fastest–growing of the major religions of the world. These circumstances raise the question of what is meant by decline. The answer as far as this book is concerned is a relative loss of wealth and power and a failure to exploit certain inventions or institutions of modernity.

Islam tried to modernise. Lewis traces some of the efforts of Muslim (principally Ottoman) reformers to reorganise their armies, economies and administrations on the lines of European states. But these endeavours, he considers, took them only so far before they came up against the problem that the West’s success depended