This major book is a treasure trove, a cabinet of wonders. Yet how does one review a Haydn encyclopedia, a task tantamount to considering the immense entirety of knowledge about this composer? It is impossible, in this small space, to do it justice, or even to refer to all ninety entries written by the sixty-seven contributors. The encyclopedia is a distinctive literary genre. It enjoys neither a monograph's authorial focus and control, nor the leisurely spaces to develop an argument afforded by an edited collection of essays. An encyclopedia is more like a labyrinth, and what it does offer is the pleasures of serendipity. Begin any entry in the Haydn Encyclopedia and, thanks to a dense network of cross-references, in small capitals, you can be whisked away to another topic entirely. Keeping your finger on the original page, you get enthralled by the new entry, forget your place, your finger slips, and up comes another rabbit hole, and away you go. Perhaps this is in tune with the desultory reading and performing practices of the late eighteenth century explored by Emily Green in a recent article (‘How to Read a Rondeau: On Pleasure, Analysis, and the Desultory in Amateur Performance Practice of the Eighteenth Century’, Journal of the American Musicological Society 73/2 (2020), 267–325). Or, to switch analogies one more time, this could be compared to the distributed scholarship of digital media: this book is a Wiki-Haydn. That said, the editors, Caryl Clark and Sarah Day-O'Connell, look back to d'Alembert and Diderot's famous example, as they explain in their helpful Preface. Given the remits of previous reference works – the Oxford Composer Companions: Haydn, edited by David Wyn Jones (New York: Oxford University Press, 2009), and Das Haydn-Lexikon, edited by Armin Raab, Christine Siegert and Wolfram Steinbeck (Regensburg: Laaber, 2010) – the editors took the decision to exclude entries on particular works, individual people and genres, focusing instead on clusters of ideas. Thus they followed d'Alembert's injunction to create ‘an overview of learning’ rather than a lives of the saints or a chronology of battles (cited on xv). The book is organized alphabetically, and, in an inspired touch, short entries, ranging in length from two to five pages, are punctuated by seven much longer ‘conceptual essays’, like pillars in a temple, which both tie together a cluster of other entries and fly their own kites.

So how does this scheme work in practice? Alas, it trips at the very first hurdle with Nancy November's entry on AESTHETICS, which I pick out for purely alphabetical reasons. Its second sentence cross-refers you to LONDON NOTEBOOKS, an entry which doesn't actually exist (there is an excellent entry, however, on LONDON AND ENGLAND, by Wiebke Thormählen). On the other hand, when November turns to ‘melodic invention’, which she holds to be at the root of Haydn's aesthetic values, there is no cross-reference to Markus Neuwirth's expert entry on MELODY. A little later, November mentions ‘lack of VOCAL training’ (1). There is no entry on ‘VOCAL’, but there is on VOCAL COACHING AND REHEARSAL, by Erin Helyard. This is careless editing. Given the central importance of melody and melodic pedagogy, why is there no entry on partimento? There are four references to partimento in the book (scattered between COMPOSTIONAL PROCESS, by Felix Diergarten, HARMONY, by Ludwig Holtmeier, PERFORMANCE, by Tom Beghin and Elisabeth Le Guin, and TOPICS, by Eloise Boisjoli and Robert Hatten), none longer than a couple of sentences, and rehearsing Haydn's report to Albert Christoph Dies of his debt to Nicola Porpora's teaching. The Cambridge Haydn Encyclopedia was published a year before Nicholas Baragwanath's The Solfeggio Tradition: A Forgotten Art of Melody in the Long Eighteenth Century (New York: Oxford University Press, 2020), a game-changer in partimento studies. See in particular Baragwanath's moving account of Haydn's musical education (28–30) and his reconstruction of Porpora's partimento regime (chapter 7). Scholarship marches on, of course, and the editors can't be blamed for that (although they might easily have commissioned an entry from Giorgio Sanguinetti and others). One could, however, imagine a living, evolving encyclopedia keeping up with the latest scholarship. A digital Wiki-Haydn, in other words, rather than a bound book.

November's opening essay also exemplifies how difficult it is to encapsulate a theme as potentially overarching as ‘aesthetics’ within a single brief entry. The General Index shows that ‘aesthetics’ is, for the most part (ninety per cent?), considered elsewhere in the volume in other entries, albeit from differing angles (see, for instance, the subsection ‘Aesthetic’ in BIOGRAPHY AND IDENTITY by Wolfgang Fuhrmann, 23). November's approach is fine, and conventionally centres on the traditional categories of the beautiful and the sublime, while touching on Haydn's proclivities for melancholy and humour. It ignores, however, the ‘operatic aesthetics’ which Caryl Clark and János Malina (THEATER AND THEATRICALITY, 371) persuasively place at the heart of Haydn's endeavours. In addition, November's claim for the centrality of melody in Haydn's aesthetics doesn't square with his abiding investment in counterpoint, especially in his string writing. Thus Laurel Zeiss (CORRESPONDENCE AND NOTEBOOKS) cites a passage from Haydn's 1768 letter concerning his Applausus Cantata in which he recommends using two violas ‘because the inner parts sometimes need to be heard more than the upper parts’ (72). Such disconnects, of which there are many in this book, are inevitable in any encyclopedia; corralling scholars can be as hard as herding cats.

The entries are also of varying quality. David Wyn Jones's page and a half on AGING is a model of clarity and succinctness, each pithy sentence written as if chiselled in stone. That said, it is innocent of the considerable medical literature on music and ageing, as is – more surprisingly – Sarah Day-O'Connell's entry on DISABILITY. Of the seven longer conceptual essays, one of the finest is IDEAS, by Emily Dolan and Matthew Head. It does a beautiful job of framing and tying up ideas from many other entries, and is full of choice phrases, such as: ‘Haydn's passions form affective constellations around the anchors of faith, the rhythms of rural life, princely magnificence, and literary-visual topoi’ (155). And its closing idea of a ‘multiple Haydn’ (165) – obviously germane to this encyclopedia – is one to run with. On the other hand, there are many entries which are far less successful. I'm not sure what Elaine Sisman's entry on TIME adds to common knowledge. RECORDING by Daniel Barolsky is mostly routine, with the few remarks about Haydn simply tacked on, and is a wasted opportunity. Andrew Greenwood's ENLIGHTENMENT lacks focus, ranging over everything that happens in this historical period, including Empfindsamkeit (already discussed brilliantly by Matthew Head) and Haydn's folksong arrangements (also extensively covered by Matthew Gelbart in FOLK SONG SETTINGS). Philip Bohlman and Rudolf Pietsch's otherwise fascinating BURGENLAND hardly mentions Haydn apart from his ‘Kaiserlied’, and is relevant only because the composer lived there. It is not obvious why Federico Celestini's perplexingly titled EXPERIENTIAL LEARNING could not have been folded into James Van Horn Melton's EDUCATION. PERFORMANCE, by Beghin and Le Guin, by far the longest ‘conceptual essay’ – at twenty-two pages, double the average length – is also narrowest in scope, being dedicated to the authors’ ‘experiment’ in rehearsal dynamics conducted at the Orpheus Institute, Ghent, in 2016 (so no discussion of tempo, ornamentation, period instruments and so forth). It should really have been published elsewhere as a self-contained article, and a less self-publicizing overview been commissioned in its stead. The essay nevertheless draws the arresting conclusion that the ideal of a sociable performance is actually extremely difficult to achieve in practice (278), because, as the authors are ready to admit (with no apparent irony), their experiment failed.

Of the 90 entries, only 14 directly engage musical notes: COMPOSITIONAL PROCESS, COUNTERPOINT, CYCLIC INTEGRATION, FOLK SONG SETTINGS, FORM, HARMONY, IMPROVISATION, MELODY, MUSICAL MATERIALS, ORCHESTRATION, RHYTHM AND METER, TONALITY, TOPICS and VARIATION AS PRINCIPLE. So, less than a sixth of the encyclopedia addresses Haydn's music; the overwhelming majority of entries are about his life. In her essay on PEOPLE AND NETWORKS, co-written with Ulrich Wilker, Clark divulges her admiration for Richard Taruskin's ‘anthropological approach to music history’ (244) and Bruno Latour's actor-network theory. This ideological commitment to the agency of Haydn is very much the guiding impulse of the entire volume. Haydn's agency, and his entanglement with the world, is absolutely everywhere in the encyclopedia, and this is not necessarily a bad thing: his agency leaps off the page. In 1765 Haydn bravely sticks his neck out to defend two musicians from bullying by the Esterházy estates manager, Peter Ludwig von Rahier (PEOPLE AND NETWORKS, 249). We see him improvising a keyboard accompaniment whilst the actor-director Joseph Kurz feigns swimming gestures (COMPOSERS AND PROFESSIONALS by Mark Ferraguto, 63). The 280 surviving letters are a rich quarry for his dealings with players, publishers and lovers. There is the celebrated letter to Maria Anna von Genzinger, in which Haydn self-consciously parodies the sentimental style with dots, dashes and exclamation marks (CORRESPONDENCE AND NOTEBOOKS by Laurel Zeiss, 72). And see his 1790 letter to Genzinger in which he reveals his hands-on attitude to vocal teaching, preferring to coach through demonstration and imitation: ‘[the sonata] contains many things which I shall analyse for Your Grace when the time comes’ (VOCAL COACHING AND REHEARSAL by Erin Helyard, 400). Haydn in London was a political symbol both of Hanoverian nostalgia for Germany and the Anglo-Austrian alliance (LONDON AND ENGLAND by Wiebke Thormählen, 200).

And yet, despite all this bustle and colour, we are still haunted by Carl Dahlhaus's deconstruction of the life/music binary in his many texts (as in chapter 1 of his Ludwig van Beethoven: Approaches to His Music (Oxford: Clarendon, 1991)). In short, for Dahlhaus, the music was the life. It falls, then, to a tiny minority of the entries to bear the load of this life within the music, and the strain shows in their density and elisions, unfairly compensating for the redundancies elsewhere in the volume. A lion's share of this heavy lifting is carried by W. Dean Sutcliffe's magisterial, Rosenesque conceptual essay on MUSICAL MATERIALS (although the essay might have been better titled ‘style’). And the density shows in the sheer concentration of Nathan Martin's superb FORM, the material of whose eight pages should really have been spread between (at least) half a dozen other entries on ‘sonata form’, ‘slow movements’, ‘minuets’, ‘rondos’ and so forth, notwithstanding the editors’ brisk explanation in their Preface of why they avoid such topics. It is worth considering how much is packed into this single gnomic sentence, which is all Martin allows for discussing Haydn's first-movement sonata forms: ‘In Haydn's instrumental music, first movements typically follow the Type 3 scheme’ (130). The reference to Hepokoski and Darcy's sonata typology suggests that their magnum opus is the covert reason why so little of the Haydn Encyclopedia deals with form: there simply is no need, and the discussion is closed. In another great entry, Ludwig Holtmeier's HARMONY, a whole book could be unpacked from this sentence: ‘inversional thinking – associated with the concept of “extensive” harmonic prolongation – plays a lesser role in his works than in those of Mozart and Beethoven’ (143). Holtmeier means that Haydn's commitment to the fundamental-bass tradition of Heinichen and Daube inhibited tonal expansion. The harmonic monumentality of the late oratorios is the exception that proves the rule, as Holtmeier concedes, representing ‘a distinct harmonic idiom within Haydn's oeuvre’ (144). The Creation and The Seasons are the focus for several contributors’ thoughts on Haydn's ‘late style’, generally on account of their sublimity (as in SUBLIME, by Keith Chapin), and yet the apparent absence of a late style (there is, pointedly, no entry on this topic) epitomizes the overall challenge of making sense of this multitudinous composer.

In some ways, the encyclopedia is an ideal genre for ‘multiple Haydn’. Unlike Bach, Mozart and Beethoven (composers surely of no less multiplicity), Haydn has never been the subject of a blockbuster life-and-works monograph. Why is that? I don't think it's purely because of our digital times. It has everything to do, rather, with the nature of his music. Something encyclopedias don't seek to achieve is to draw the strands together, a task which is the remit of an author or, indeed, a reviewer. Many of the strands in the Cambridge Haydn Encyclopedia lean in the direction of musical mimesis, which they consider under different rubrics: MIMESIS itself (Annette Richards); pictorialism (NATURE, by Elaine Sisman); operatic text setting (LIBRETTOS AND LIBRETTISTS, by Pierpaolo Polzonetti); the imitation of human behaviour (SOCIABILITY, by Edward Klorman); and, in general, a realism which, according to Raymond Knapp, made Haydn's music ‘intractable’ to German Idealism (IDEALISM, 151). Knapp singles out the notorious bassoon ‘fart’ in Symphony No. 93 as the emblem of Haydn's realism (152). But most of all, Haydn's intractable realism is epitomized in opera, not because it aspires to any anachronistic ‘verismo’, but because the genre sets texts and stories – and this upsets our prevailing image of Haydn as fundamentally an instrumental composer. Thus Clark and Malina are absolutely right to emphasize that underpinning Haydn's multiple enterprises was ‘a binding aesthetics of theatricality and spectacle’ (THEATRE AND THEATRICALITY, 371). So here is our problem: opera was Haydn's most important genre, he thought his operas were his best work, and yet we don't much like his operas. Otherwise put, we will never get our heads round Haydn until we come to terms with the realities that instrumental genres (symphonies, quartets and sonatas), the basis of his modern prestige, were at the bottom of the eighteenth-century's hierarchic system of values (BIOGRAPHY AND IDENTITY by Wolfgang Fuhrmann, 23); that he subscribed to this value system; and that he believed that his operas comprised his greatest achievements. Until we ‘get’ his operas, a synoptic monograph on Haydn will not be possible. And perhaps we never shall. In the absence of that, we can be grateful to Clark and Day-O'Connell for assembling such a rich and stimulating, if necessarily pointillist, portrait of this joyful composer. What better way to pass lockdown than to curl up and lose yourself in the Haydn Encyclopedia.