On reflection, my imagined Hindu litigator would have been as likely to play the 'If you can't beat them join them' card. His polytheism isn't really polytheism but monotheism in disguise. There is only one God — Lord Brahma the creator, Lord Vishnu the preserver, Lord Shiva the destroyer, the goddesses Saraswati, Laxmi and Parvati (wives of Brahma, Vishnu and Shiva), Lord Ganesh the elephant god, and hundreds of others, all are just different manifestations or incarnations of the one God.

Christians should warm to such sophistry. Rivers of medieval ink, not to mention blood, have been squandered over the 'mystery' of the Trinity, and in suppressing deviations such as the Arian heresy. Arius of Alexandria, in the fourth century AD, denied that Jesus was consubstantial (i.e. of the same substance or essence) with God. What on earth could that possibly mean, you are probably asking? Substance? What 'substance'? What exactly do you mean by 'essence'? 'Very little' seems the only reasonable reply. Yet the controversy split Christendom down the middle for a century, and the Emperor Constantine ordered that all copies of Arius's book should be burned. Splitting Christendom by splitting hairs — such has ever been the way of theology.

Do we have one God in three parts, or three Gods in one? The Catholic Encyclopedia clears up the matter for us, in a masterpiece of theological close reasoning:

As if that were not clear enough, the Encyclopedia quotes the third-century theologian St Gregory the Miracle Worker:

Whatever miracles may have earned St Gregory his nickname, they were not miracles of honest lucidity. His words convey the characteristically obscurantist flavour of theology, which — unlike science or most other branches of human scholarship — has not moved on in eighteen centuries. Thomas Jefferson, as so often, got it right when he said, 'Ridicule is the only weapon which can be used against unintelligible propositions. Ideas must be distinct before reason can act upon them; and no man ever had a distinct idea of the trinity. It is the mere Abracadabra of the mountebanks calling themselves the priests of Jesus.'

The other thing I cannot help remarking upon is the overweening confidence with which the religious assert minute details for which they neither have, nor could have, any evidence. Perhaps it is the very fact that there is no evidence to support theological opinions, either way, that fosters the characteristic draconian hostility towards those of slightly different opinion, especially, as it happens, in this very field of Trinitarianism.

Jefferson heaped ridicule on the doctrine that, as he put it, 'There are three Gods', in his critique of Calvinism. But it is especially the Roman Catholic branch of Christianity that pushes its recurrent flirtation with polytheism towards runaway inflation. The Trinity is (are?) joined by Mary, 'Queen of Heaven', a goddess in all but name, who surely runs God himself a close second as a target of prayers. The pantheon is further swollen by an army of saints, whose intercessory power makes them, if not demigods, well worth approaching on their own specialist subjects. The Catholic Community Forum helpfully lists 5,120 saints,¹⁸ together with their areas of expertise, which include abdominal pains, abuse victims, anorexia, arms dealers, blacksmiths, broken bones, bomb technicians and bowel disorders, to venture no further than the Bs. And we mustn't forget the four Choirs of Angelic Hosts, arrayed in nine orders: Seraphim, Cherubim, Thrones, Dominions, Virtues, Powers, Principalities, Archangels (heads of all hosts), and just plain old Angels, including our closest friends, the ever-watchful Guardian Angels. What impresses me about Catholic mythology is partly its tasteless kitsch but mostly the airy nonchalance with which these people make up the details as they go along. It is just shamelessly invented.

Pope John Paul II created more saints than all his predecessors of the past several centuries put together, and he had a special affinity with the Virgin Mary. His polytheistic hankerings were dramatically demonstrated in 1981 when he suffered an assassination attempt in Rome, and attributed his survival to intervention by Our Lady of Fatima: 'A maternal hand guided the bullet.' One cannot help wondering why she didn't guide it to miss him altogether. Others might think the team of surgeons who operated on him for six hours deserved at least a share of the credit; but perhaps their hands, too, were maternally guided. The relevant point is that it wasn't just Our Lady who, in the Pope's opinion, guided the bullet, but specifically Our Lady of Fatima. Presumably Our Lady of Lourdes, Our Lady of Guadalupe, Our Lady of Medjugorje, Our Lady of Akita, Our Lady of Zeitoun, Our Lady of Garabandal and Our Lady of Knock were busy on other errands at the time.

How did the Greeks, the Romans and the Vikings cope with such polytheological conundrums? Was Venus just another name for Aphrodite, or were they two distinct goddesses of love? Was Thor with his hammer a manifestation of Wotan, or a separate god? Who cares? Life is too short to bother with the distinction between one figment of the imagination and many. Having gestured towards polytheism to cover myself against a charge of neglect, I shall say no more about it. For brevity I shall refer to all deities, whether poly- or monotheistic, as simply 'God'. I am also conscious that the Abrahamic God is (to put it mildly) aggressively male, and this too I shall accept as a convention in my use of pronouns. More sophisticated theologians proclaim the sexlessness of God, while some feminist theologians seek to redress historic injustices by designating her female. But what, after all, is the difference between a non-existent female and a non-existent male? I suppose that, in the ditzily unreal intersection of theology and feminism, existence might indeed be a less salient attribute than gender.

I am aware that critics of religion can be attacked for failing to credit the fertile diversity of traditions and world-views that have been called religious. Anthropologically informed works, from Sir James Frazer's Golden Bough to Pascal Boyer's Religion Explained or Scott Atran's In Gods We Trust, fascinatingly document the bizarre phenomenology of superstition and ritual. Read such books and marvel at the richness of human gullibility.

But that is not the way of this book. I decry supernaturalism in all its forms, and the most effective way to proceed will be to concentrate on the form most likely to be familiar to my readers — the form that impinges most threateningly on all our societies. Most of my readers will have been reared in one or another of today's three 'great' monotheistic religions (four if you count Mormonism), all of which trace themselves back to the mythological patriarch Abraham, and it will be convenient to keep this family of traditions in mind throughout the rest of the book.

This is as good a moment as any to forestall an inevitable retort to the book, one that would otherwise — as sure as night follows day — turn up in a review: 'The God that Dawkins doesn't believe in is a God that I don't believe in either. I don't believe in an old man in the sky with a long white beard.' That old man is an irrelevant distraction and his beard is as tedious as it is long. Indeed, the distraction is worse than irrelevant. Its very silliness is calculated to distract attention from the fact that what the speaker really believes is not a whole lot less silly. I know you don't believe in an old bearded man sitting on a cloud, so let's not waste any more time on that. I am not attacking any particular version of God or gods. I am attacking God, all gods, anything and everything supernatural, wherever and whenever they have been or will be invented.