For many of us, the computer is the symbol of our hypermodernity, the image of how vastly we differ – culturally, economically, socially, and politically – from past generations. And many of us think of our hypermodernity as a phenomenon of the 1990s, when PCs became fixtures in our homes, and the Internet became one of our primary means of communicating, working, shopping, playing, and even procrastinating.

But the idea of the computer is old indeed, traceable to a largely forgotten Victorian inventor named Charles Babbage. Doron Swade’s The Difference Engine: Charles Babbage and the Quest to Build the First Computer tells the story of Babbage’s lifelong dedication to the idea of the computer, from the moment in 1821 when he exclaimed that mathematics ought to be powered by steam, until his death half a century later, a slightly addled old man still hard at work on his eternally evolving designs. Swade’s book also tells the story of his own dedication to Babbage’s vision: The final third of The Difference Engine describes how, as curator of computing at London’s Science Museum, Swade finally finished the work Babbage began over 150 years ago.

A classic curmudgeonly polymath who was known – with good reason – as “The Irascible Genius,” Babbage was an inveterate, obsessive tinker, a mathematician with a penchant for engineering that led him, over the course of his long and colorful life, to invent such varied items as the opthalmoscope, the cowcatcher found on the fronts of locomotives, the blackbox recorder (for trains), a submarine automated by compressed air, a seismograph for measuring earthquakes, a “coronograph” for generating artificial eclipses, a pen that drew dotted lines (for mapmaking), ergonomic paper (green ink on green paper, Babbage found, was easiest on the eyes), and a pair of shoes designed to let the wearer walk on water (Babbage nearly drowned when testing them, thus establishing that his considerable mental powers did not extend to working miracles).

When he wasn’t busy inventing, Babbage dabbled in cryptography, wrote books of social criticism, and raised insult to an art form – the irascible genius was known for his ability to alienate people, and honed his talent on everyone from the Royal Society (which he attacked in a scurrilous book on how governmental corruption was contributing to the decline of English science) to street musicians (who met Babbage’s persistent efforts to silence them by playing loudly right outside his window).

But Babbage’s pet project, the thing that absorbed, goaded, and thrilled him for his entire adult life, was a machine that would compute. Spurred to invention by the chronic inaccuracy of human calculation, Babbage’s idea was to take large-scale computation out of the forgetful, distractible heads of people (usually low-paid, largely uneducated drudges) and put it in the far more efficient and reliable cogs and levers of mechanism. Determined to design a machine that would not only do perfect calculations but print out error-free tables of results as well, Babbage secured governmental funding and went to work. Over the next several decades, he designed what he called “The Difference Engine” again and again, making each incarnation more efficient, more elegant, and more compact than the one before, and leaving a trail of unfinished efforts in his creative wake.

Between inadequate funding, disputes with contractors, and Babbage’s almost sublime ability to abandon incomplete projects, the Difference Engine was never built. Indeed, by the 1840s, Babbage had moved on to an even more ambitious machine that he called the “Analytical Engine.” The Analytical Engine was never built, either, but in theory anyway it represented a substantial advancement over the Difference Engine. A programmable machine with memory and a central processor, capable of looping and conditional branching, the Analytical Engine possessed many structural elements of the modern digital computer.

Dismissed as a crackpot during his own lifetime and subsequently forgotten by all but the most enthusiastic computer buffs and obsessive Victorianists, Babbage has been relegated to the footnotes of history, a curious example of a man whose ideas were too far ahead of his time to make sense. Conventional wisdom states that even if Babbage had tried harder to see his project through to completion, neither the Difference Engine nor the Analytical Engine could have been successfully built for the simple reason that Victorian manufacture was not up to the task. Babbage’s original Difference Engine, for example, called for 25,000 separate parts, many of which had to be perfect duplicates of one another: an impossible job in an era before standardization enabled identical, interchangeable parts to be mass produced. A hundred years of history has it that there was simply no way a machine so complex could have been made to workable specifications when every last one of its components had to be forged and filed by hand. But that, Swade argues, is exactly where history has been wrong.

When Swade became curator of computing at the Science Museum in 1985, he was surprised to discover that no one had ever actually tested the hypothesis that Babbage’s machines could never have worked. Swade vowed to build one of Babbage’s machines by the bicentennial of his birth, and pledged to do so using only technology that would have been available to Babbage himself. He fixed on Difference Engine #2 as the most viable design (it is the only one of Babbage’s many models for which complete plans exist). And then he set about the long, arduous process of procuring funding, putting together a team of engineers and contractors, and finally building the Engine itself.

Swade’s curatorial odyssey makes up the final third of the book. With its tales of evaporating funding, mountainous paperwork, endless unforeseen mechanical dilemmas, and looming deadlines, it is a fitting conclusion to Babbage’s saga, not just because it vindicates the inventor’s unerring faith in his designs (Difference Engine #2 works like a dream) but also because it dramatizes how readily we can still be derailed by the forces that derailed Babbage himself.

The difficulties Babbage faced during the mid-19th century were in many ways the same ones that Swade faced at the end of the 20th century. For both men, funding was a problem: Then as now, the Difference Engine, for all its computational efficiency, was very far from a cost-effective design. And for both men, the sheer expense of the venture meant doing battle with the red tape, rank egoism, petty politics, and chronic imaginative myopia that characterized bureaucracy then as now. Because many private and public donors are every bit as self-serving and profit-minded today as they were a century ago, and because creative projects without obvious commercial applications still don’t compete well for sponsorship, the Difference Engine almost didn’t get built this time around either.

But Swade is a better politician than the bridge-burning Babbage was, and he was finally able to summon both the substantial financial backing and intense media interest necessary to make the project fly. An irony: It was the state that pulled Babbage’s funding when he became too troublesome to deal with, and it was the state that finally came up with the money for Swade to prove Babbage right. An even greater irony: In proving Babbage right, Swade proved history wrong. The Victorians did have the capacity to build a computer. What they didn’t have was the vision to see why they should want to.

Few besides Babbage truly grasped the need for a machine that could be programmed to perform, and then print, massive quantities of calculations in a short amount of time. Babbage’s was a world on the edge of informational overload, a steam-powered society that, for all its instinctive appreciation for how well machines could take over certain repetitive human actions, could not yet fathom why anyone would want to outsource a repetitive form of thought – calculation – to a swift, accurate and tireless machine. We will never know what kind of impact Babbage’s engines might have had if they had been built. What we do know is that between Babbage’s confrontational personality and his culture’s unimaginative conservatism, a potentially transformative historical event never took place.

Swade has made it possible for us to know that Babbage’s is a story of intellectual, rather than technological, limitation; of missed opportunity rather than misguided engineering. And thanks to Swade, we have now to revise a chapter of our history, to replace the familiar narrative of Babbage’s curious prescience with a less quaint but far more telling account of the systematic incompetence that prevented Babbage’s vision from being realized. And we have to take to heart the lessons that revision teaches us: about the chronic human tendency to dismiss what we don’t understand; to leave unfinished what we begin; to allow petty squabbles to interfere with the collective pursuit of a greater good. Our digitized world looks very different from that of the Victorians. But our natures are no different from those of our forebears, and our capacities for spectacular shortsightedness are as great as ever.