The Marketplace of Christianity is an awkward, misleading title. The book should have been called "The Economics of Religion", for that is its subject. Admittedly it is focused principally on the Protestant battle to win market share from the Roman Catholics in the Middle Ages, and it analyses the economics of this holy war with great skill. But it also touches on many other religions, attempting to promulgate general economic tenets that might apply to all of them - and in this it is far less successful.
Perhaps surprisingly, the study of the economics of religion is not new. Adam Smith discussed religion at length in The Wealth of Nations . But after Smith there was a two-century hiatus until, in 1975, the subject was resurrected by Corry Azzi and Ronald Ehrenberg in their economic study of church attendance. Since then, it has won many converts.
Like Adam Smith, Robert Ekelund, Robert Hebert and Robert Tollison are determinedly non-judgmental about religion. They rightly believe it is not their role, as economists, to approve or disapprove of religion - and even by the end of the book it is impossible to be certain whether or not they are believers. Their creed is that human beings have always needed, and will always need, non-material explanations of the material world - initially magical, primitive explanations, which later morphed into more spiritual, religious explanations.
This is the basis of their attempt to generalise about religions. "No urge, primal or modern, is more fundamental than the desire to explain existence," they sermonise. Codswallop. The selfish gene's primal urges are the survival of self and the survival of the species. "Explaining existence" is an intellectual activity in which Homo sapiens indulge only when they have sufficient food, shelter and sexual fulfilment to leave time for metaphysical musing.
The authors see religion, first and foremost, as a provider of cerebral solace. They consider religion's main offering to be belief in an afterlife. Human beings have an innate need for an afterlife, they say - a need as real as their need for sustenance. Similarly, they lay great emphasis on religions' ability to help humans cope with what they call "existential terror", claiming that: "Existential terror will not disappear no matter how far science takes Homo sapiens." All this is codswallop, too.
Neither Richard Dawkins nor I can live without sustenance. But both of us - and many tens of millions of others - can and do live perfectly well without believing in an afterlife. Nor do all religions bother much with an afterlife. Judaism is hardly concerned with the hereafter at all.
And while some aspects of some religions may temper existential terror, others positively inflame it. Their religion must have plunged most Mayans into paroxysms of existential terror (it certainly should have done); and what is fear of hell but an ever-present threat of existential terror in the afterlife?
Fortunately, the authors are much better at dealing with specific examples of economics at work than at such grandiose generalities. In The Marketplace of Christianity they provide numerous sharp and relevant instances of economic forces influencing religious practices. Their analysis of the economics of selling indulgences is masterful. Their account of why, in 1966, the Pope had to change the rules governing the eating of fish on Fridays - as Cardinals from heavy meat-eating countries became more influential in the Vatican - is downright heavenly. So is their comparison of the size and cost of Roman Catholic versus Protestant cathedrals. These and many other topics show the economics of religion to be a discipline well worth having faith in.
But in concentrating on human beings' cerebral responses to religion the authors fail to grasp the fact that religious activity is often an end in itself. Take the Jews' refusal to eat milk and meat together. Theologians have foisted purposeful meanings on this, but it has no purpose or meaning.
It is a meaningless rite. Religions are full of them. And while the authors devote a chapter to religion in Ancient Egypt, Islam is hardly mentioned - a surprising omission in the 21st century. Perhaps this, too, reflects the authors' unwillingness to come to terms with ritual. Ritual is very strong in Islam. Being called to prayers five times a day dominates Muslim life.
But this is not cerebral either: the activity is its own justification.
The authors' stated unwillingness to bring psychology into their studies is, I suspect, at the root of the problem. Religion is far more complex and nebulous than the goods and services with which economics typically deals.
So understanding the psychology of religion will be critical to a fuller understanding of the economics of religion. The Marketplace of Christianity contains many pertinent case histories. But if it is to achieve its full potential, the discipline will demand much more, and much deeper, psychological insight.
Winston Fletcher is chairman, The Royal Institution.
The Marketplace of Christianity
Author - Robert B. Ekelund Jr, Robert F. Hebert and Robert D. Tollison
Publisher - MIT Press
Pages - 355
Price - £19.95
ISBN - 0 26205 082 X