What particularly excites Silvia Ferrara, the author of The Greatest Invention, is not language per se but writing – that is, the specific tool created for recording and conveying language visually. Sound made visible, tangible. The impulse to communicate might be innate, but writing is cultural, and in no way inevitable. It’s a bit of tech, which needed to be developed, and which needs to be learned. Writing has many obvious benefits – allowing communication to survive across time, thus enabling cultural traditions and posterity – unlike purely synchronous conversation, face-to-face, stuck in the present. Yet as a species (and a species with memory, specifically) we could live perfectly well without it, as indeed we did. Writing is only about 5,000 years old, but we’ve been talking for about 200,000.

Ferrara reveals to us (using writing) the conditions under which this invention took place. Though perhaps, she says (writes), we should be thinking in terms of discovery rather than invention – and in any case, shouldn’t it be inventions, plural? Because whatever we might have been taught, writing is not a cultural gadget that was invented/developed/discovered once, in one place – cuneiform in Mesopotamia, perhaps – and then spread helpfully across the rest of the world. Rather it sprung up in many places, often quite independently, under conditions that can be very hard to generalise. Some writing systems were born out of large developing cities and states (writing that seems at first glance to have emerged out of bureaucracy, essentially); but then you have those that showed up on small islands, with a function that’s altogether different. Writing systems may have commonalities, but it’s hard to pin down any qualities in their development that are universal.

The main players are Egypt, Mesopotamia, China and Mesoamerica, writing’s four major birthplaces (China’s being the only one of these still in use). But Ferrara tells the stories of many other individual scripts, in so far as we know them. We see the ingenuity of their evolutions (usually beginning with iconicity, developing into something more agile and linear like an alphabet) and, with very few exceptions, their decline (the question of what makes certain scripts endure is fascinating). And there’s such range – even Incan quipus, devices for recording information comprising arrangements of knotted threads. Are they ‘writing’ as we commonly understand it?

Amid these multiple not-quite-parallel histories, Ferrara makes time for bigger-picture, more abstract questions. Not least, what is a script anyway? Because even the experts don’t always concur. To Ferrara, the highly complex Rongorongo found in carvings on Rapa Nui constitute a script, but some colleagues disagree. In the book we find much praise of cross-disciplinary collaboration – the only way of solving the big mysteries, with palaeography, linguistics, archaeology, etc. all joining forces – but also more than a few digs at academia and academics, not just for confirmation bias or lack of rigour but especially for a competitive and distinctly uncollegial refusal to play nicely with the other children.

The Greatest Inventionis filled with seeming digressions – why is Ferrara telling us about copper on Cyprus, defining the nature of the state and extolling the pleasures of list-making? – but which turn out always to be there for a reason. It is brisk, simple to follow and unfussy – though the author has a way with a helpful metaphor, for which we non-experts are grateful. Only occasionally does it turn complicated; but this is where much of the fun is to be found. Old rediscovered scripts are presented as puzzles – as codes that need deciphering. Historically some have been easy enough to crack (especially if we know the language they’re representing, or if there is a large amount of it – the more data, the easier it is to find patterns and deduce rules). Others remain all but impossible, with almost a dozen scripts still awaiting revelation. Nearly half of these – such as the misnamed Cretan Hieroglyphic, or Linear A – first appeared on islands. Ferrara asks why that might be, too.

Some of the liveliest parts of the book describe the thrill of this deciphering, or the methods that might lead to it. We are earnestly advised not to try this at home (or if we must, please don’t write to her with our crackpot theories), but it’s hard not to be infected by the enthusiasm when we meet Ferrara’s own research group Inscribe – the Invention of Scripts and their Beginnings. And the appephering impulse is understandable when the outstanding gaps in this book’s story prove just as pleasing as its more definitive expositions. Alongside, say, Sequoyah’s brilliance and persistence in developing the Cherokee syllabary, which had clear political motives, we have Hildegard of Bingen’s weird migraine-induced creation of an alphabet, the purpose of which was… well, we have no idea. Ditto the as yet unexplained Voynich Manuscript and the Phaistos Disc.

Ferrara’s book is an introduction to writing as a process of revelation, but it’s also a celebration of these things still undeciphered, and many other tantalising mysteries besides.