With this volume, the Catholic theologian Hans Küng has completed the trilogy with began with his `Judaism' in 1991, followed by his `Christianity' in 1994. Each of these three books is arranged in a similar way, dividing the history of each religion into Paradigms, the shift from one Paradigm to another coming about chiefly through major historical events which forced corresponding changes in the intellectual history of those faiths. There is no need to be scared by this slightly pompous conceptual framework: the story is clear even without it. As Küng himself admits, there is a difference between paradigms in science (to which Thomas Kuhn applied the concept in the first place) and paradigms in religion. While it does not take long for a new paradigm in science totally to replace an earlier one, in the history of religion, old paradigms retain an extraordinary vitality even after new ones have been established; so that, for instance, in the Moslem world the intellectual notions of Muhammad's Islam and of the Islam of the medieval Caliphates still powerfully challenge those of more modern forms of Islam.
As he goes along giving an account of the development of Islam, Küng frequently makes comparisons with the developments in Judaism and, in particular, in Christianity, pointing out similarities and differences. Perhaps because he is a Roman Catholic, he is particularly interested in the comparison between al-Ghazali and Thomas Aquinas, to which he devotes many pages, while being very much briefer about Avicenna and Averroës, in whom most western writers have been more interested than in al-Ghazali. Küng's case for this disparate treatment is that unfortunately the former two, for all the influence they would have on Western thought, had no lasting influence in Islam.
Küng is not afraid of praising and of criticizing Islam: there is a particularly outspoken criticism of Islam when, at the end of the 12th century, that great and high-achieving civilization turned its back on further philosophical or theological developments. Its last great thinkers had far more influence on the West (which learnt a great deal from the Arabic `Renaissance') than they had on the Islamic world. The West went on to construct, on the base of the Arabic Renaissance, a Renaissance of its own, while the Islamic world did not experience a further Renaissance, nor a Reformation or an Enlightenment. The Scientific Revolution (which contributed so much to the development of technologies in the West) had no parallel in Islam, which had been preeminent in mathematics, medicine and science during its golden age. As a result the Islamic world was in due course humiliated by the greater might of the European powers.
But between the end of the Arabic Renaissance and that humiliation, there were some powerful Islamic empires - the Moghuls of India, the Safavids of Persia, and especially the Ottomans. The greatest weakness of Küng's book is that these three empires receive very cursory treatment. In particular there is no examination whatever of what made the Ottoman Empire so successful for some four centuries.
Only when the dynamism of the West impinged on the Islamic world in the 19th century did some Islamic thinkers make an attempt to modernize Islamic thought, though meeting great resistance. Indeed, because the modernizers were unable to protect the Islamic world against western political and then economic imperialism - and were indeed often accused of colluding with it - the traditional thinkers of Islam were able to identify their cause with angry nationalism, and so were able to gain even greater influence.
Rejecting the ideology of `a clash of civilizations', Küng is passionately interested in how, without fudging difficulties, the differences between Islam and the West and between Islam and the other two Abrahamic religions can be bridged. After 470 pages of describing the history of Islam, he devotes the remaining 190 pages largely to reflections on this topic. The suggestions he has for reducing the political tensions (for example about the Arab-Israeli issue) is fairly run-of-the-mill for those who are looking for the `reasonable' solutions that men of good will should be able to achieve.
As for his ideas about how the theological tensions between Judaism, Christianity and Islam might be reduced, he points out that the Hellenistic doctrines of the divinity of Jesus and of the Trinity became official Christian teaching only in 325 at the Council of Nicaea; and he suggests that all the three Abrahamic faiths should be able to find common ground in the Jewish Christianity of the time of Jesus. Yet he affirms that he himself accepts the decisions of the Councils of Nicaea and Constantinople and is not suggesting that Christians should reject them. But if they don't, I can't see myself where the common ground would be in this area.
What might also help to establish common ground would be if the Muslims could see the Qur'an in the way that all but fundamentalist Christians and Jews now see the Bible (and as the suppressed Mutazilites of the 9th century once did): as divinely inspired, but created by human beings who have interpreted the inspiration in the historical context in which they lived. But Muslim exponents of such ideas (and Küng names several such) still run great dangers in the Islamic world.
Though Christianity has long had a bad record of intolerance, barbaric punishments, and subjection of women, it does now subscribe to the doctrine of human rights; and common ground between the religions would require that those Islamic countries which still do not respect human rights should reform. Similarly, Christianity has abandoned its military crusading mission, and there can be no common ground with those Muslims who still interpret jihad not simply as sanctioning the use of force in defence of Islam, but also as the duty to expand its rule by force.
In his conclusion Küng expresses his `unshakable hope' ... `that all three world religions together will [N.B. not `can'] make an indispensable contribution to a more peaceful and more just world.'