Robert MacSwain’s 2013 Solved by Sacrifice offered readers a compelling examination of Austin Farrer’s epistemology; the role of saints bracketed that work. The introduction stated, ‘one major advantage of Farrer’s position is the place it provides … for the epistemic value of “saints”’ (p. 9); the conclusion added, ‘So the saint is our evidence’ (p. 225). The 2013 work pointed towards saints as divine evidence but left the argument undeveloped. More than a decade later, MacSwain has developed it in the present volume: a marvelous work that makes, as the subtitle indicates, a ‘hagiological argument for the existence of God’.

The genre of this work is not easily defined. It is an exercise in analytic philosophy of religion, but MacSwain finds that discipline unnecessarily narrow and expands it by bringing in unusual voices, especially from Christian theology. After discussing Swinburne and Plantinga, his argument ‘culminates’ (p. xii) with Rowan Williams and Stanley Hauerwas. MacSwain also draws on ethics, church history, comparative religion and cultural studies. From these diverse disciplines, he comes up with twenty definitions of sainthood. Readers seeking an apology for the essential definition will be disappointed. While MacSwain evaluates the different definitions, he refuses to defend one.

The work is divided into three parts: 1. Evidence, 2. Sainthood, and 3. The Hagiological Argument. The first part begins with a comprehensive survey of the epistemic arguments for God’s existence that narrows into the importance of ‘aristocratic evidence’, a phrase from Farrer that epistemically privileges the lives of saints. Wittgenstein’s influence is brought to bear on Farrer’s argument. For Farrer, rather than ‘logical demonstration’, saints’ lives connect ‘religious symbols and everyday realities’. MacSwain adds, ‘There is an interesting parallel here with Wittgenstein’s remark: “The way to solve the problem you see in life is to live in a way that will make what is problematic disappear”’ (pp. 55–56). The second part demonstrates how broadly sainthood matters for all the disciplines mentioned above. Interest in sainthood is a ‘global phenomenon’ (p. 147). MacSwain does not invent the argument; it exists in everyday life. He offers judicial counsel concerning the global phenomena of sainthood that his definitions represent. Some are ‘too narrow, some are too broad, some are directly relevant to the argument, and some are not’ (pp. 147–148). The third part draws on the relevant definitions for the hagiological argument. MacSwain sets forth three versions of it: the propositional, perceptual, and performative. Each has its own ‘integrity’, but they also share a ‘family resemblance’ (p. 157). Sarah Coakley and Alexander Pruss are his primary interlocutors for the propositional, Peter van Inwagen for the perceptual, and Hauerwas and Williams for the performative. While each version plays its part in his hagiological argument, MacSwain indicates a preference for the performative.

A crucial question posed is ‘whether the hagiological argument is just an argument about saints or whether saints themselves are the “argument”’ (p. 257). If it is the former, then the saints would fit within a broader argument that might draw upon probability calculations from Bayes’ theorem or inference to the best explanation. If it is the latter, no such broader argument is necessary. I think it is safe to say that MacSwain holds primarily to the latter position. It is why his argument ‘culminates’ with Williams and Hauerwas. In that sense, it is a ‘subjunctive’ argument for God’s existence, one that takes no comfort in certainty. This also raises a difficulty. If faithful lives render God credible, then unfaithful lives, especially once thought faithful, are counterevidence. MacSwain contrasts saints with ‘stains’ and does not shy away from drawing attention to the failures of Karl Barth, John Howard Yoder, John Paul II and Jean Vanier. Are the failures of once perceived saints, demonstrable arguments against divine existence? It is possible, and MacSwain does not seek to quantify how many saints, or how much sanctity, would be necessary for a convincing demonstration of divine existence. This work is not that kind of argument. It points in new directions but refuses to tie everything up.

MacSwain suggests three future directions for the hagiological argument. First is simply to be attentive to ‘actual saints by those concerned with the normative evaluation and truth of religious beliefs’. Second is to acknowledge that identified saints are too male and too European. More attention should be given to those from a ‘distinctively contemporary mode and who emerge from different social backgrounds and gender identities’. Finally, the ‘hagiological argument’ deserves to be more fully studied and developed (pp. 265–266). Analytic philosophy of religion and Christian theology and ethics would do well to heed MacSwain’s counsel.