The 1975–1979 corpus splits cleanly into two imaginative registers when it comes to personal transportation in 2025, and the split is itself the finding. On one side, Gerard O'Neill designs elaborate, frictionless mobility systems for space habitats — commuterspheres, magneplanes, travelspheres — where the engineering problem of transportation has been essentially solved. On the other, Joseph Weizenbaum looks at the same period from Earth and sees the private automobile as a cautionary exhibit: a "cultivated and finally addictive hunger" that computers enabled rather than replaced, producing "millions of trivial options on new cars" instead of the mass transit alternatives that were technically available all along. Mark Adlard's Multiface occupies the uncomfortable middle — a near-future Britain where electric autos exist, stratified by class, navigated through incomprehensible interchange maps, still fundamentally cars.

What none of them saw coming was the particular shape of 2025's transportation reality: the private automobile survived, electrified and increasingly autonomous, but without the social transformation that either O'Neill's optimism or Weizenbaum's critique implied. Weizenbaum was right that computers would be used to elaborate the car rather than transcend it — but he couldn't have predicted that "millions of trivial options" would eventually include the option to have the car drive itself, collapsing the distinction between private vehicle and transit system in ways that confound both his critique and O'Neill's alternatives. The electric runabout in Adlard's habitat, recharged at Autoterminus stations, is recognizably a Tesla — but Adlard placed it in a rigidly class-stratified world where the gleaming silver model costs two months of increments for a one-way trip between sectors.

Adlard's detail about the "New Autocomplex" map — a traffic interchange so labyrinthine that protagonist Will cannot parse it, "a bloated spider in the middle of a web too intricate for unravelling" — is perhaps the most precisely accurate image in the corpus. The infrastructure complexity these authors were living inside in the 1970s didn't go away. It calcified. The 2025 driver navigating a GPS-guided route through a mid-century interchange is still, fundamentally, inside that spider web. The intelligence moved from the driver to the device; the web remained.

Clarke's prediction in The View from Serendip that improved communications would reduce commuting — "a future in which men do much less commuting, much more communicating" — half-landed. The pandemic briefly made it true, and then employers largely reversed it. His autonomous mobile home, freed from utility connections and able to migrate seasonally, remains science fiction, though the RV-as-primary-residence has become a visible 2020s phenomenon for a specific economic cohort priced out of fixed housing.

[Gerard K. O'Neill, The High Frontier, 1977] contributes the era's most technically specific transportation vision, and it's entirely off-Earth. The commutersphere, magneplane, and travelsphere form a coherent system predicated on abundant cheap electricity, vacuum environments, and computer-controlled scheduling. What's striking in retrospect: O'Neill's space commuter gets more comfort, more autonomy, and lower cost-per-mile than any Earth traveler. The implicit argument is that Earth's transportation problems are solvable — just not on Earth, where aerodynamic drag, petroleum dependence, and infrastructure inertia make every solution a compromise. His "few minutes on the magneplane, a half-hour flight in a travelsphere" for less than a round-trip car journey reads today as both prescient about what's technically achievable and completely wrong about where it would happen.

[Joseph Weizenbaum, Computer Power and Human Reason, 1976] is the sharpest analyst in the corpus on why transportation didn't transform. His argument isn't that the technology failed — it's that computers were used to optimize existing structures rather than enable new ones. "The private automobile could have been downgraded as a means of personal transportation in favor of mass transit... but the computer was used to automate the flow of parts to automobile production lines." In 2025, this reads as essentially correct, with one ironic extension: the computer eventually did transform the car — into an electric, connected, semi-autonomous vehicle — but the car itself remained the unit of transportation. Weizenbaum's critique anticipated Uber more than it anticipated the subway renaissance.

[Mark Adlard, Multiface, 1975] provides the most granular street-level (or autoway-level) texture. His future Britain runs on electric autos hired at Autoterminus stations with credit cards — a functional description of a car-share scheme with EVs. The class stratification is vivid: the rectangular black box with no doors versus the silver spaceship-on-wheels that costs two months of wages for a one-way trip. His "How To Drive An Auto" booklet, which Will studies for months, captures the friction of adoption — new technology requiring new literacy, unevenly distributed. The gas turbine vehicle in passage 9, running 200,000 kilometers without maintenance in "total silence," anticipated the reliability expectations now attached to EVs, even while getting the propulsion technology wrong.

[Arthur C. Clarke, The View from Serendip, 1977] contributes two things: the communications-substitutes-for-transportation thesis, and the honest acknowledgment that infrastructure has enormous inertia. "The road and rail systems will still be basically the same," he writes about 1992, and extends the logic: capital-intensive physical systems change on generational timescales regardless of incentives. This is the most durable insight in the corpus. The 2025 US highway system is still recognizably the Interstate system of the 1970s. Clarke also floats the autonomous mobile home — freed from utility infrastructure — which hasn't arrived but whose logic appears in contemporary off-grid and van-life movements.

The corpus reveals a fork in the road that the 1970s could sense but not resolve: would computation transform transportation by transcending the car, or by elaborating it? Weizenbaum argued the latter was happening already and would continue. O'Neill bet on transcendence — but relocated it to space, where the constraints didn't apply. Adlard split the difference with a future that still has cars, just electric and hired rather than owned. Clarke thought communications would make the question moot by eliminating much of the need to move at all.

What actually happened was a synthesis none of them quite envisioned: the car survived, electrified and networked, while communications did reduce some commuting without eliminating it, and the infrastructure inertia Clarke identified proved as durable as he predicted. The magneplane never came to Earth; Weizenbaum's "addictive hunger" for private vehicles proved correct; Adlard's electric hire-cars arrived but were called Zipcars and then Lyfts; Clarke's comsole became the smartphone that now navigates the very traffic jams he hoped to make obsolete. The 2025 reality is every 1970s prediction simultaneously, partially true.

This corpus is almost entirely male, Western, and — with the exception of Weizenbaum's critique — techno-optimist in its baseline assumptions. The voices missing are those who experience transportation not as an engineering problem or a philosophical question but as a daily survival constraint: the worker in Adlard's Second Sector who can't afford the hire charges, the commuter Weizenbaum mentions but doesn't give a voice to, the populations in the Global South for whom neither the private automobile nor the magneplane is the relevant frame.

The corpus also has no fiction set in cities that aren't implicitly London, New York, or a space habitat modeled on American suburbs. The 2025 transportation revolution most consequential for the largest number of people may be the electric motorcycle and tuk-tuk in Southeast Asia, or the e-bike in Chinese cities — none of which these authors were positioned to imagine. O'Neill's space habitats are, in a sense, the ultimate gated community: transportation perfected for a self-selected population that has already escaped the constraints everyone else is still living inside.