If P.G. Wodehouse were to write an introduction to philosophy of religion, and if he were any good at analytical philosophy, this is the book he might have produced. Mawson addresses his imagined reader in a witty and intimate style, regaling us with hilarious anecdotes—featuring butlers, straight bananas, space-ships and complaints about the government—which do double-service as philosophically probing thought experiments. Aimed effectively at an undergraduate audience, the great virtue of the book is that it does not simply introduce students to the main lines of argument and critique (although that it does), but it encourages the reader to think, by showing how a philosopher might approach an issue, with an interest not so much in the literature about it, but in the questions of truth that the literature is about. Also admirable is the way in which Mawson advances an original position, so making it of wider interest to the more advanced reader.

Mawson sets out by making the case for the coherence of the traditional concept of God. As one would expect—this being the ‘traditional’ concept—much of the material does not lend itself to much original treatment, with accounts of what it means to call God personal, transcendent, omnipresent, omnipotent, omniscient, perfectly good and necessary. Nonetheless, Mawson's treatment displays more nuance than most, by the illuminating way in which he argues that God is ‘more personal than any other person could ever hope to be’, and by the way in which he pairs incorporeality with transcendence, and immanence with omnipresence. What theists are trying to articulate when they talk of God's incorporeality, Mawson argues, is best understood as the claim that ‘every part of the physical world is one he knows about directly and every part is one he can control directly’ (p. 27), such that the better term here would be ‘transcendence’ (p. 27). Omnipresence is best unlocked by the concept of immanence because God ‘is not in any way ignorant of it or unable to control it by direct acts of his will’ (p. 27). Also superior in Mawson's treatment is the way in which God does not just happen to have this particular list of properties: he demonstrates how they emerge conceptually from the one ‘essential property’ of God, ‘his being the most perfect person that there could be’ (p. 68), such that all the properties ‘are best seen as merely facets of this property of divinity’ (p. 68).

Mawson wraps up the question of immortality elegantly. Rather than rehearsing the rather tired slugging match between dualists and materialists, he approaches the issue from a realist/anti-realist perspective. The anti-realist considers that ‘once we know all the facts about where the matter of our bodies has gone and what properties are instantiated’ (p. 99), then there is ‘nothing we don't know about the world, just perhaps something we've yet to decide about words’ (p. 99). The realist considers that ‘once we know all the facts about where the matter of our bodies has gone and what properties are instantiated … there's still something that we may know about the world’ (p. 99); either because ‘there's more to the world to us persons—than the matter of our bodies … and this truth must be … a truth about a spiritual substance, a soul’ (p. 99), or because ‘there really is a correct percentage of matter/form or perhaps a tiny particle or somesuch in one's brain that can't be destroyed finally if one is to survive’ (p. 99).

Whichever way you look at it, Mawson suggests, there can be no in principle problem with the claim that we can survive bodily death. If, following an anti-realist line, identity is a matter of linguistic convention, then providing that ‘enough people in some heavenly realm decide to use the appropriate words in the right way’ (p. 99), which God could easily bring about, we could ‘survive’ in the available sense. If you take the realist line, then God could either ensure the survival of the soul, or make sure that the ‘right percentages are instantiated in Heaven’ (p. 99). This approach is likely to drive anti-realists and materialists potty: the complaint might well be that only a realist could reduce anti-realism to being a claim about the consensus of language users constructing truth; similarly, the materialist might complain that the sheer logical possibility of God maintaining souls or percentages of identity is a long way from the persuasiveness of the doctrine of the immortality of the soul, against the broadly naturalistic mood of contemporary philosophy of mind. But Mawson's preparedness to be controversial is precisely what makes Belief in God more interesting than your average ‘some people say x, some people don't’ introduction: the gauntlet is thrown down for the anti-realist to say where they have been misconstrued, and to the materialist to face the suggestion that if sheer logical coherence is permitted as the benchmark for ‘possibility’ in other branches of philosophy (as it frequently is), then it should also be allowed in philosophy of religion.

Rather than just charging into the traditional arguments for the existence of God, Mawson encourages the reader to reflect on what constitutes a good argument. In the process, there are some excellent introductory accounts of the underdetermination of theory by data, and the role of simplicity in evaluating explanations. The illuminating discussion concludes that a good argument ‘is one the premises of which make its conclusion more probable than not and the premises and reasoning of which are more obviously correct than is the conclusion’ (p. 119). Mawson dispatches quickly the suggestion that belief in God might be properly basic: at least it could hardly be so for anyone reading this book to whom the thought that there might not be a God is presumably not unheard of (p. 121). Mawson then proceeds to show that the ontological argument, the argument to design and the cosmological theory are not in the sense outlined good arguments.

The refutations are all well-done, frequently offering a refreshing take on these well-thumbed proofs. The discussion of the ontological argument contains within it about as good an introductory account of Frege's distinction between abstract and concrete objects that one could hope for (p. 129ff). So we avoid the text-book tendency to report that ‘existence is not a predicate’ on the rather baffling grounds that ‘it doesn't make a difference whether something exists’. Hume is extensively treated, and nicely taken apart: even if the argument to design does not work, it does not not work for the reasons that Hume offers. At the heart of Mawson's critique of the argument to design is his intuition, which is perhaps one of the more controversial points of the book, that the existence of an infinite number of worlds is a simpler explanation of fine-tuning in the universe, than the existence of a single God. This because simplicity of type is preferable to simplicity of tokens of type: positing an infinite number of universes posits only ‘one type of thing, universes’ (p. 150), whereas positing God and one universe involves only two tokens, but also two types of thing. The thought experiment used to back up this intuition might be too rushed for some. We are asked to imagine the familiar room full of monkeys writing early drafts of Shakespeare plays. One person suggests the hypothesis, ‘There's an infinite number of monkeys sitting at typewriters’, whilst another suggests ‘there's a finite number of monkeys and at least one non-monkey thing sitting at typewriters’ (p. 151). ‘Which would you favour?’, Mawson asks, replying on our behalf: ‘surely you would favour the former hypothesis, even though it posits infinitely more tokens than the latter, which posits one more type’ (p. 151).

The danger with thought-experiments of course is that the dullard to whom they are addressed might not jump the right way. And here I found myself such a dullard: presented with a Shakespeare play, I would lean every time towards the suggestion that there was a Shakespeare in the room, rather than more flipping monkeys. Although convinced that Mawson is correct that there is a problem with straightforwardly announcing God to be the ‘simplest’ explanation, the monkeys didn't do it for me.

Mawson shows effectively that the game is not quite up yet, in that the theist can fall back on the cosmological argument. Even if there is an infinite number of universes, it might be that this is the contingent fact that requires explanation. Mawson does a fine job of showing that the ‘Principle of Sufficient Reason’—which motivates this search—is not constitutive of rationality, and ‘begs the question against physicalism’(161). The argument from religious experience does better under Mawson's analysis. Using Swinburne's ‘principle of credulity’—that ‘if it seems to a subject that something is the case, then—all other things being equal—it is reasonable for him or her to believe that it really is the case’ (164)—Mawson dwells skilfully on the analogy of the sighted man in the Kingdom of the blind, to suggest that it is reasonable to believe one's own religious experiences, and to accept the testimony of others. As we'd expect, given this conclusion, reports of miracles are allowed to ‘contribute something to an inductively sound cumulative case argument for the existence of God’ (p. 194). Penultimately, the problem of evil is dealt with by a blend of fairly traditional considerations: the value of freedom, and the hope that individuals will be compensated for their suffering in the afterlife.

On a popular Radio 4 satirical quiz-show in the UK, I'm Sorry I Haven't a Clue, there is a round known as ‘one song to the tune of another’. The studiedly cynical presenter Humphrey Lyttelton explains the rules of this patently self-explanatory exercise every time with an analogy as baffling as it is complicated. So, for example: ‘imagine the song as a leg, and the tune as a pair trousers. But I know what you are thinking teams: what about the awkward zip and the pens in the pocket that dig into your thighs when you sit on the bus? …’, and so on for a minute or two. Mawson has a real genius for the clarifying analogy, and ninety-five percent of the time, they are used to great pedagogic and philosophical effect. Just occasionally, perhaps, he enjoys the analogy too much, and it becomes more complex than the argument it is clarifying.

Perhaps this becomes a problem in the most controversial part of the book, Mawson's final defence of belief on the basis of Pascal's wager. Traditionally, this is found to be a rather distasteful approach, because so nakedly instrumental about avoiding punishment, and maximising potential reward. Any anxieties about the lack of reverence or profundity in this approach will probably not be alleviated by Mawson's extensive and intricate analogy of betting at the horse-races, which for this reader at any rate, was to Pascal's wager, rather like the rules to ‘one song to the tune of another’. What we need in the case of Pascal's wager is not an explanation of the principle of rationality on which it works, which is capable of infinite complexification, but the nerve of which is all too straightforwardly about avoiding bad things and securing good things. Rather, we require very convincing grounds not to throw out such a self-serving and calculating principle of rationality completely when thinking about God. If we believe in God, then presumably one of the things we also believe is that there is more to life than securing our own comfort.

More profound and intriguing in Mawson's concluding chapter, is his suggestion that prior to settling the issue of God's existence, it is worthwhile praying, because, if the argument of the book is correct, one has reason to believe that such a process will help us towards true beliefs: either for or against the existence of God, although Mawson considers the former more likely. The suggestion that one can only come to believe in God if one puts oneself into an attitude of prayer, has a deep and venerable tradition of spiritual direction behind it. Mawson's attempt to integrate such advice into a sophisticated contemporary epistemology is admirable. I ended the book wanting to hear much more about this, with a suspicion that for this idea to flourish, it would need to be disentangled from the Pascalian language of ‘pay-offs’.

This is not the book for those wanting to learn about the classical and medieval roots of philosophy of religion, or for those seeking exposure to continental approaches. Indeed, Mawson says as much right at the beginning. But for those seeking an introduction to the philosophy of religion in the analytical tradition, you could hardly do better than Mawson's book. To an unusual extent for an introductory work, Belief in God makes you think, and at times provokes strong assent or dissent. It even makes you laugh, not sometimes but often. Anyone working in the analytical tradition of philosophy of religion, at any level, would find something of interest in the book: both as teaching material (I know from experience how much students enjoy some of the thought experiments), and as a contribution in its own right.