In this volume Paul Janz addresses what is arguably one of the most fundamental methodological questions for theology: how can human discourse refer meaningfully to a transcendent God? He conceptualises this perennial question as a twofold demand for integrity: a demand for the integrity of reason (or rational integrity) and a demand for the integrity of transcendence (or revelational integrity).

Janz summarises his thesis as follows: ‘The aim of this present study is to preserve integrity on both levels: that is, without being drawn into the extremes at either end, to which emphasis of one kind of integrity at the expense of the other will invariably lead’. Janz labels the extremes he seeks to avoid Positivism and Reductionism. Reductionism fulfils the demand for rational integrity at the expense of revelational integrity. Reductionists explain religious phenomena in naturalistic terms by means of the various projection theories – Freudian, Feuerbachian, etc. Positivism, on the other hand, fulfils the demand for revelational integrity at the expense of rational integrity. Positivists give religious transcendence a ‘perceiver-independent supremacy and autonomy’ and in so doing ‘posit’ that revelation is authoritative over matters of reason and yet immune to the objections or demands of reason.

Crucial to Janz's argument is the notion of integrity. Janz realises that the notion of integrity (in either its rational or its revelational varieties) assumes the existence of intrinsic rational obligations. After explaining rational and revelational integrity in chapter 1, in chapter 2 Janz discusses those who deny the existence of intrinsic rational obligations. He finds such a position flawed because those who hold it ‘cannot respond to the demands of integrity implicit in the claim to orthodoxy’. Even among those who accept the existence of intrinsic rational obligations, there is deep disagreement on how these obligations should be understood. Against this backdrop, in chapter 3, Janz discusses the perennial debate between realism and anti-realism, which Janz expresses as the disagreement over whether human sensation or intellect should be given priority in philosophical inquiry. In the course of his discussion, he considers the work of the two pre-eminent exponents of these positions, Hilary Putnam and Thomas Nagel, and in chapter 4 seeks to advance the discussion by utilising the insights of Donald MacKinnon's ‘conciliatory realism’. While Janz finds neither realism nor anti-realism entirely satisfactory, he notes a preference for realism.

In chapter 5, Janz broadens the discussion by considering another of ‘philosophy's perpetual polarities’: the polarity between act and being. On this matter, Janz discusses the work of Dietrich Bonhoeffer who approached this debate with distinctively theological purposes in mind. In doing so, however, Janz comes to an impasse. Every attempt to speak meaningfully about God, to preserve both rational and revelational integrity, runs aground on one or another of philosophy's perpetual polarities: realism/anti-realism; act/being. Consequently, Janz concludes that if progress is to be made on this matter, some other way of conceptualising the question must be found. Janz locates the seeds of this reconceptualisation in Kant's ‘empirical realism’. In chapter 6, Janz seeks to correct some of the many misinterpretations of Kant. According to Janz, when Kant is properly understood, he reformulates the requirement for theological reference as a new kind of demand for finality that allows a genuine realism without the pitfalls of onto-theology.

While Janz finds that Kant sets us on the right path, he does not bring us to our final destination. Kant leaves God as a ‘hypothetical transcendent’. In chapters 7 and 8, Janz reformulates Kant in order to allow for the more robust sense of reference that he deems is required by meaningful discourse about God.

This volume is impressive in its scope. Janz moves with facility between the fields of philosophical theology, systematic theology and history of philosophy, discussing such disparate thinkers as Richard Rorty, Karl Barth and Jean-Luc Marion and uncovering many impressive insights along the way. The scope of Janz's project, however, makes it difficult to assess. Many of the aspects of his argument are set in the context of readings of a variety of other thinkers. For example, as noted previously, Janz approaches the realism/anti-realism debate through the dual lenses of Putnam and Nagel. At one level this is illuminating: not only is the realism debate clarified, so are the respective positions of Nagel and Putnam. At another level, however, Janz's approach is less helpful. At one point in his treatment of realism, Janz refers to the contributions of Nagel, Putnam, Hegel, Berkeley, Wittgenstein and MacKinnon, all in less than two pages. The problem is that some of Janz's interpretations of these figures are less than uncontroversial. The result is that the difficulty of the realism debate is compounded by the difficulty in understanding ‘Hegel on realism’.

Perhaps, however, this critique is not entirely fair. When addressing a topic as difficult as the referentiality of religious language, no approach is perfect. Despite its foibles, Janz's volume is a worthy contribution to the perennial debate on how to understand language about God.