It’s easy to underestimate what goes into compiling an index. It involves incredible amounts of skill, knowledge and effort to do justice to the task. An index, after all, involves a special kind of writing, and furthermore demands a rigorous and methodical person, someone with a nuanced understanding of how to make a text more accessible to a reader. It’s no coincidence, then, that to be an ‘indexer’ is a specialist job, and that one can learn to create indexes professionally. So, is indexing an art or a science? You could make a case for either interpretation.
The Society of Indexers says that ‘the skill of indexing lies in analysing the document, identifying indexable terms and concepts, and creating appropriate headings’. The words ‘analyse’ and ‘identify’ – even the word ‘index’ itself – sound rather scientific. Indexing involves mechanical tasks, which are now often completed using specialised software that requires no special human creativity. There are also certain elements that all professional indexes will have in common. Indexers will invariably arrange their index in alphabetical order – not something that has always happened. A scribe from the Middle Ages, for instance, might have annotated his texts with little symbols – a system developed by Robert Grosseteste, Bishop of Lincoln and Chancellor of the University of Oxford, in the thirteenth century – with each symbol signifying a distinct subject. Such systems were not at all common, however, before page numbers were introduced in the late fifteenth century. Page numbers are now also a ‘must’ to help any indexer locate terms. The ability to make use of categories and sub-categories, numerical order and cross-referencing are all requirements of an indexer, too, and they must be consistent throughout any index. So far, so ‘sciency’.
But an index is more than a series of standardised elements and locators, which could be relatively simply automated by computer. A reader using an index compiled by a computer might be uncertain about the information they have been given. Is it relevant? Is it complete? While artificial intelligence is on the rise and clearly has many functions, it is not (yet) a substitute for human judgement and experience. It cannot (yet) understand how a reader engages with a text. These are resolutely human activities, part of an art. Skilled indexers can work with a wide range of documents, and seemingly miraculously anticipate how readers will use them. They’ll be able to figure out the points of entry to a text, ascertain which ones are suitable for each audience, and decide how to lead readers to particular terms and their respective locations. A professional indexer is capable of working like this across disciplines that require subject specialist knowledge – legal and medical texts, general non-fiction and textbooks. Indexers even make higher-level choices, taking decisions on style and length and how to make an index user-friendly. It’s worth remembering that, particularly if a book is an academic text produced for an audience of scholars, librarians, lecturers and so on, a reader might go straight to the index. And it’s right there, in that list of words and numbers that a book’s primary audience will decide its worth, and whether it merits their attention.
A good index, then, is like a map. It tells the reader what they are to expect on the road up ahead, its twists and turns, and even the scenery they might pass. And creating a map is an apt analogy for creating an index. Cartography is clearly a scientific endeavour. But it’s also a piece of art, beautiful in not only its function, but also its form.