In 1941 an ambitious Philadelphia pediatrician, the wonderfully named Waldo Emerson Nelson, became the editor of America’s leading textbook of pediatrics. For the next half-century the compilation of successive editions of this large volume advanced his career, consumed his weekends, and encroached heavily on his domestic life. Every few years, when a new edition was being prepared for the press, he would dragoon his family into assembling the index for him. He would read through the proofs of all 1,500 or so pages, calling out the words and concepts to be listed, while his wife, Marge, and their three children—Jane, Ann, and Bill—wrote down on index cards the thousands of entries and their corresponding page numbers.

Though Nelson was a brilliant physician, even his most admiring colleagues were struck by his “austere and stern” appearance, his “façade of gruffness,” his “granite conviction of right and wrong.” “Whenever I talk to my residents,” he once proudly recounted about his treatment of junior doctors, “they never know whether to laugh or cry. That’s the way I like it.” So it’s not surprising to find that when his teenage children complained about their indexing duties, he responded by printing the following dedication at the front of the 1950 edition of what became known as the Nelson Textbook of Pediatrics:

Recognizing that children, like adults, prosper under the stimulus and responsibility of a task to be done,
the contribution that this book has made to
in providing them such privileges, and the satisfaction in family living which has come from group activity

Nowadays we take for granted that any kind of learned book should be indexed, however tedious the labor. So valuable is this tool, so central to our ways of thinking about and using information, that in the case of multivolume scholarly editions of texts, it’s not uncommon for the index itself to constitute an entire book. Yet in the classical world the concept of such a search aid was unknown. To Cicero, an “index” meant a label affixed to a scroll that indicated its contents, rather like the printed spine or dust jacket of a modern volume on a bookshelf. As Dennis Duncan notes in his clever, sprightly Index, A History of the, the rise of the index in its current form is a story of many interrelated developments, each with its own contingencies and chronology: the replacement of scrolls by the codex, the triumph of alphabetical order, the rise of new pedagogies and genres of learning, the invention of print, the adoption of the page number, and the constantly changing character of reading itself.*

Take alphabetical order. Even though the consonantal alphabet had been around since the early second millenium BCE, the earliest known examples of its application as an organizing principle date only from about the third century BCE. The now lost 120-scroll catalog of the Library of Alexandria listed authors partly in alphabetical order. That the ancient Greeks were fond of using it is evident in everything from their fishmongers’ price lists to records of taxpayers and monuments to playwrights (the background panel of one surviving marble statuette of Euripides lists the titles of his plays from alpha to omega).

Yet after them the Romans largely disdained the alphabetical principle as arbitrary and illogical, and so did Europeans throughout the Middle Ages. Books about words—like lexicons, grammars, and glosses—employed it, but it was not a widely understood rule. As late as 1604 the first printed dictionary of English, Robert Cawdrey’s A Table Alphabeticall, was obliged to begin by explaining that its readers should attend to

the Alphabet, to wit, the order of the Letters as they stand…and where euery Letter standeth: as (b) neere the beginning, (n) about the middest, and (t) toward the end. Nowe if the word, which thou art desirous to finde, begin with (a) then looke in the beginning of this Table, but if with (v) looke towards the end. Againe, if thy word beginne with (ca) looke in the beginning of the letter (c) but if with (cu) then looke toward the end of that letter.

The term “index” didn’t come to be used in its current sense in English until quite recently. There’s no entry for it in Cawdrey, while Samuel Johnson’s Dictionary of the English Language (1755) defined it as “the table of contents to a book.” For centuries words like “table,” “register,” and “rubric” were used interchangeably for what we now call indexes and contents pages: only very gradually, over the past two hundred years or so, have the two forms come to be regarded as essentially distinct. (The related Anglophone convention that indexes appear at the back of books and contents pages at the front seems to have been part of a similar, relatively recent process of separating them.) Nonetheless, names aside, the alphabetical index as a type of textual technology turns out to be much older than that.


There are two basic types, which in modern books are usually combined into a single list. One type collates words, the other concepts. The former is a concordance, the latter a subject index. The first is the kind of literal, specific listing of entries that you can get your computer to produce by using CTRL+F for any word or phrase in a text; the second is the product of a more subjective, humanistic attempt to capture the meanings and resonances of a work. Duncan, understandably, is mainly interested in the evolution of the latter type—even though, because of the rise of the word-based online search engine, we now find ourselves living in a golden age of the concordance. But the two forms need to be treated together, he argues, because both were invented at the same time and place: in northwestern Europe, in or around 1230.

The index was, in fact, part of an entire range of organizational and reading tools that were conceived in the thirteenth century. (Others included the division of the Bible into standard chapters and the genre of distinctiones, a new kind of search aid for preachers that helpfully grouped together biblical extracts on the same subject.) Two social developments at this time created a novel demand for information to be organized in rapidly accessible ways: the foundation of the first European universities and the rise of the new orders of mendicant friars, with their stress on the frequent and engaging preaching of God’s word. In Oxford the scholar and cleric Robert Grosseteste (so named, it was said, because of his gigantic brain) compiled an enormous subject index to the whole of the world’s knowledge, to aid him and his students in navigating it all. His Tabula, of which only a fragment survives, encompassed the entirety of the Bible, the writings of the Church Fathers, the works of classical authors like Aristotle and Ptolemy, and Islamic authorities including Avicenna and al-Ghazālī.

Meanwhile, in Paris, the Dominican Hugh of Saint-Cher (soon to become the first person ever to be painted wearing reading glasses) oversaw the compilation of an even more stupendous alphabetical word index. This was the first concordance to the Bible, listing over 10,000 of its keywords with all their locations, from the exclamation “A, a, a” (now usually translated as “ah!”) all the way to “Zorobabel,” the sixth-century-BCE governor of Judea.

Soon enough, medieval readers were making their own indexes to volumes they owned. The invention of printing brought further refinements. Page numbers had already been used to number the leaves of individual manuscripts, but the uniformity of printed books gave them a different utility, as a means of referring to the same place across different copies of the same work. It took time for this idea to catch on. The first printed page number was not produced until 1470; even by 1500 only a small minority of books had adopted the practice. Instead, early printed indexes referred to textual locations or to the signature marks at the bottom of pages (“Aa,” “b2,” and the like), which printers and binders used to keep their finished sheets in the correct order. But in the course of the sixteenth century, use of the page number spread, alongside the creation of increasingly sophisticated indexes by scholarly authors.

As early as 1532, Erasmus published an entire book in the form of an index because, he quipped, these days “many people read only them.” A few years later his colleague Conrad Gessner, one of the greatest indexers of his day, rhapsodized about how this new search tool was transforming scholarship:

They are the greatest convenience to scholars, second only to the truly divine invention of printing books by movable type…. Truly it seems to me that, life being so short, indexes to books should be considered as absolutely necessary by those who are engaged in a variety of studies.

Like every widely observed change in reading and learning habits before and since (the invention of writing, the launch of Internet search engines, the spawning of ChatGPT), the spread of the index was accompanied by anxiety that flighty, superficial modes of accessing information were supplanting “proper” habits of reading and understanding. In the sixteenth century Galileo complained that scientists seeking “a knowledge of natural effects, do not betake themselves to ships or crossbows or cannons, but retire into their studies and glance through an index or a table of contents.” To “pretend to understand a Book, by scouting thro’ the Index,” jibed Jonathan Swift in 1704, was the same “as if a Traveller should go about to describe a Palace, when he had seen nothing but the Privy.” Yet as Duncan wisely points out, our intellectual habits are always changing, and for good reason. Every social and technological shift affects how we read—and we also all read in many different ways. Twitter, novels, text messages, newspapers: each demands a different kind of attention. The older we get, the more invested we are in modes of reading that we’re familiar with and the more suspicious of technologies that seem prone to disrupt them.


The eighteenth century produced a great efflorescence of indexing novelties, jokes, and experiments, which Index, A History of the has great fun cataloging. For a while it seemed as if indexes might become part of almost every genre of writing, including epic poetry, drama, and novels; the inclusion of an index had become a literary status symbol, a sign that a text was prestigious or that a book had been lavishly produced. Alexander Pope’s multivolume, best-selling translation of the Iliad, which earned him a fortune, included several grand, exhaustive, and intricate tables and indexes (including one listing the emotions in Homer’s work, all the way from “Anxiety” to “Tenderness”).

In the 1750s Samuel Richardson produced an eighty-five-page index to his enormous novel Clarissa. (It included its own index to the index.) This wasn’t really a reference for the main text, but more like a summary of the moral lessons contained in the original, seven-volume, million-word monster of a book. He called it “a table of sentiments” or (to give it its full title) “A Collection of such of the Moral and Instructive Sentiments, Cautions, Aphorisms, Reflections, and Observations, contained in the History of Clarissa, as are presumed to be of General Use and Services, digested under Proper Heads,” and toyed with the idea of publishing it separately as a work in its own right. But Richardson, who started out as a printer, was an outlier in his love of indexing (he also later produced a huge unified index to all three of his novels), and this proved to be a largely abortive branch of literary evolution. After all, names and facts are rather easier to index than thoughts and feelings.

Instead, by the nineteenth and twentieth centuries the textual forms of fiction and nonfiction had grown increasingly distinct. The latter were ever more energetically and impressively indexed. In the 1850s Jacques Paul Migne’s monumental collection of the writings of the Church Fathers, in 217 volumes, was accompanied by an equally humongous four-volume index, which was produced by a team of more than fifty laboring for over a decade and was itself divided into no less than 231 parts. There were indexes by author, subject, title, date, country, rank (popes before cardinals, cardinals before archbishops, and so on), genre, and hundreds of other categories—including separate indexes to heaven and hell.

Toward the end of the century, librarians from around the world combined forces to produce a universal, international index of all the most important books and knowledge in existence—as well as, on a more modest but still extraordinary scale, the first global indexes to the flood of periodical publications. In modern fiction, on the other hand, indexing by this time largely appeared only as a literary conceit: a play on genre, fictionality, and facticity. Both Vladimir Nabokov and J.G. Ballard wrote stories that used the index form (in both of which the last entry, at the end of the Z’s, reveals a final twist of the plot).

Duncan is a brilliantly illuminating and wide-ranging guide across this richly varied terrain, though his cast of characters remains overwhelmingly male. He notes in passing that since the 1890s, with the emergence of secretarial agencies, indexers have been largely female, and that today they are overwhelmingly so—including the compiler of his own book’s fine index, Paula Clarke Bain. Unfortunately he doesn’t pursue the point. Yet the gendered, patriarchal hierarchy of labor through which twentieth-century scholarly indexes were commonly produced is fascinatingly evoked by the prefaces to countless books of the era.

In 1983, at the conclusion of his monumental eleven-volume edition of the diary of Samuel Pepys, the lead editor, Robert Latham, compiled what is often regarded as the finest index ever produced in English. Thirteen years earlier, the first volume in the series had appeared in harrowing circumstances: just as it was going to press, his wife, Eileen, to whom he had been married for thirty years, suddenly died. “The late Mrs Robert Latham read many of the proofs,” the anguished editor recorded at the end of his acknowledgments, in the standard, buttoned-up phraseology of midcentury male academic prose. “Beyond that, she gave help which can never be measured.”

By the time he composed the acknowledgments to the index volume, Latham had happily remarried, and the sexual revolution had passed even through Cambridge. His remarks now conjured a more relaxed, less overtly chauvinist world—as well as providing an appealing vignette of familial indexing in practice:

My wife Linnet has shared in the making of this Index. I laid down the ground plan, but she involved herself in every process of its construction. She read aloud the entire text of the diary while I took notes—discussing with me, as we went along, exactly what words might best introduce the successive groups of references, and thus converting what might have been a chore into a paper-game. At later stages she undertook innumerable investigations into detail, and checked from the text every reference in the typescript.

“As a joint enterprise with his wife’s energy and powers of organization, and with a text so entertaining,” he elaborated to the Society of Indexers,

the work in fact often spilled over into hilarity, becoming a game rather than a job. Indeed indexing itself may be seen as a word game, seeking the appropriate word for comprehensive headings or verbal formulas for a whole series of related subjects; Mrs Latham’s expertise in word games accounted for many of their solutions found.

Not every such marital collaboration around this time was as harmonious. In the mid-1970s the new lead author of America’s standard textbook on obstetrics, Jack Pritchard, asked his wife, Signe, to prepare the index for him. They had been married for thirty years. She was a nurse, a mother, and a feminist who had recently changed her title to “Ms.”; his textbook was suffused with attitudes toward women and their bodies that evidently infuriated her. When the index appeared, it turned out that she had included the line “Chauvinism, male, variable amounts, 1–923” (i.e., on every page of the book). Four years later, for the next edition, she improved this to “Chauvinism, male, voluminous amounts, 1–1102” and added, for good measure, another judgment on the whole enterprise: “Labor—of love, hardly a, 1–1102.”

Perhaps she had heard about the Nelson Textbook of Pediatrics. A few months after Ann Nelson’s father completed the sixth edition of his book, she went off to college. On graduating in 1954 she wed an aspiring lawyer, Richard E. Behrman. Before agreeing to marry him, he later recalled, “Ann made him promise never to ask her to help him write a textbook.” But within a few years, as the seventh edition neared completion, her domineering father demanded that Ann (now referred to as “Mrs. Richard E. Behrman”) and her siblings once more rally around to help him make its index. So she did—and paid him back by adding an entry of her own. Under “Birds, for the,” she listed the entire book, pages 1–1413. Never cross your indexer.