This volume of eight essays presents Denys Turner as a teacher. All but one of the essays were first given as university talks or lectures; and, as even a brief perusal of the Contents page indicates, Turner is not concerned in this volume with tackling one or two big topics in exhaustive detail, but, rather, with a broad range of topics, each very substantial in itself: God and evil, prayer and the darkness of God, faith and reason, medieval biblical hermeneutics, science and religion, the thought of Marguerite Porete and of Herbert McCabe. And what an excellent teacher Turner is. For a start, he is expert at constructing dramatically satisfying theological narratives in engaging and accessible prose. Opposing views or an intellectual impasse are first presented, with Turner presenting ways forward by invoking the thought of favoured theologians, in particular Aquinas.

But Turner's ability as a pedagogue is perhaps most evident when he explains complex and subtle ideas using simple comparisons. Take, for example, the use of the music of Mozart to explain the fittingness of the existence of sin within the story of salvation (Julian of Norwich's ‘sin is behovely’). Mozart's music, we are told, is ‘supremely unpredictable’; and yet as the music progresses each new note seems just right, to the degree that looking backwards the music now seems ‘supremely retrodictable’ (p. 19). Just listen to the opening movement of Mozart's Piano Concert No. 20 in D minor, K.466, to appreciate the aptness of Turner's example.

Or, consider how Turner makes the case for the importance of the Catholic doctrine of transubstantiation (entailing that the substance of the bread is not present in the Eucharist, but has been transformed into the Body of Christ) against the Lutheran doctrine of companation (the real presence of Christ in the Eucharist alongside the unchanged substance of the bread). To most Catholics this distinction is obscure and irrelevant. But in the context of discussing the thought of Herbert McCabe, himself an outstanding teacher and noted Thomist, Turner supports McCabe's view that we cannot fully understand the human meaning of food unless we understand its Eucharistic depth. The Eucharist has metaphysical and explanatory priority. And so Turner insightfully points out: ‘The Eucharist is not the presence of Christ as an add-on meaning of eating and drinking together: it is the meaning of eating and drinking together’ (p. 153, italics not added). Companation undermines the metaphysical and explanatory priority, whereas transubstantiation does not; and Turner deftly shows why.

Yet, in one, and admittedly only one, essay, ‘Reason, the Eucharist, and the Body’, I thought that Turner's relatively broad canvas approach was problematic, though the essay still has considerable merit. Here Turner argues not only that Aquinas believed that the existence of God is rationally demonstrable; but that even if all the attempted proofs of the existence of God thus far fail as rational demonstrations, it remains the case that we should accept that such rational demonstration is in principle possible. This is clearly a contentious position in the context of contemporary philosophical theology; and it should be noted that Turner has backed down from the stronger claim about the role of reason in theology that he previously defended in his 2004 book, Faith, Reason, and the Existence of God, that the Fathers of the First Vatican Council had solemnly declared as de fide that the existence of God is rationally demonstrable.

To illustrate the position he argues for, Turner gives the example of Fermat's last theorem, the (corrected) proof of which was published in 1995 (see p. 46). Just as this theorem was (let us assume) known to be true even when unproven, and thus for Turner it seems to follow that there had to be in principle a proof of the theorem, so too, Turner suggests, since we can know that God exists, then in not dissimilar fashion there must surely be a demonstrable proof of God's existence.

I accept that there is an intuitive plausibility to the claim that if we accept the truth of Fermat's last theorem then it follows that there must in principle be a proof for it. But this is to rely on the intuitive plausibility of a claim that I could also imagine mathematicians arguing about: that there must be a proof for every possible true mathematical theorem. To be fair to Turner, he does not use the Fermat's theory example as the basis of a proof for his position on faith and reason. But a more revealing problem is that the grasp of the proof of Fermat's last theorem, being a deductive proof, requires simply the ability to engage with advanced mathematics, whereas Turner's case in favour of the in principle rational demonstrability of the existence of God turns out to go beyond the specificity of such straightforwardly deductive reasoning to incorporate a much more inclusive conception of reasoning.

My concern is not that Turner proceeds in this direction. It is, rather, that I sensed an under-addressed tension throughout the essay between two different views: God's existence as rationally demonstrable along the lines of a deductive proof (and thus the sort of proof that should convince anyone without conceptual or factual error and who possesses the intellectual capacity to engage with the methods of proof used) and God's existence as rationally demonstrable in ways that require engaging with the world in terms that include meaning and value (and thus the sort of proof that would require some element of receptivity to, and appreciation of, the transcendentals of goodness, truth, and beauty).

It also concerns me that Turner makes a number of claims that are disputable and insufficiently argued for. Turner, for example, states: ‘I cannot see Thomas Aquinas being much disconcerted by the nonequivalence of the divine names, philosophy proving God under one description, faith believing another…’ (p. 50). Even if this is largely correct, say, such ease of assertion is problematic given some of Aquinas's own remarks, such as: ‘Belief in God as descriptive of the act of faith is not attributable to unbelievers. In their belief God's existence does not have the same meaning as it does in faith. Thus they do not truly believe in God’ (ST 2a2ae 2, 2 ad.3; translation by TC O'Brien). Turner also frequently (e.g., pp. 51, 52) assumes that faith entails knowledge. This is presented without both the subtle qualifications found in Aquinas and the sort of explanation and justification that those shaped by modern epistemology might seek.

Had these concerns been raised in the Q&A following the talk or lecture, I expect that Turner would have given helpful and enlightening responses. In any case, my concerns are few and for the most part minor in the face of a multitude of virtues. A number of the essays can be read as expertly delivered summaries of key ideas and arguments found, albeit sometimes in different form, in some of Turner's most important books: Julian of Norwich, Theologian; Faith, Reason and the Existence of God; and, to a lesser extent, The Darkness of God (Essays 1, 3, and 6, respectively). This book is thus a wonderful introduction to the thought of Denys Turner as well as the topics he addresses. I was sorry when I came to the end of this book. It was like being in the company of a highly insightful and exceptionally engaging teacher for a couple of hours.