The 1975–1979 corpus splits cleanly into two registers when you point it at personal transportation in 2025: one register is orbital and utopian, the other is terrestrial and diagnostic. What makes the split interesting isn't the disagreement — it's that both registers were right, and about completely different things.

O'Neill's High Frontier imagines commuting as a solved problem, the moment you leave Earth behind. His "commutersphere" and "magneplane" aren't vehicles so much as arguments: that the friction of terrestrial transport — aerodynamic drag, petroleum dependency, cramped conditions, complex maintenance — is a product of being stuck on a planet's surface, not an intrinsic feature of moving people between places. The magneplane runs through vacuum at 300 mph, requires no engines, and carries people on computer-controlled schedules so frequent that timetables become irrelevant. The travelsphere between cylinders costs nothing to operate because it uses the habitat's rotation as its power source. O'Neill's transportation vision is frictionless in the most literal sense. What's striking from 2025 is how precisely he identified the correct problems — petroleum dependency, aerodynamic inefficiency, schedule rigidity — while projecting their solution entirely off-planet.

Weizenbaum, writing from the same moment, looks at the same automobile system and sees something O'Neill doesn't: that the computer, rather than transcending the private car, was being used to entrench it. His passage about automobile production lines is one of the sharpest observations in the corpus — that computational power was deployed to give consumers "millions of trivial options on their new cars" rather than to build mass transit or meaningfully differentiate vehicles. This is not a failed prediction. It is a description of 2025. The configurator on every major automaker's website is the direct descendant of what Weizenbaum was already identifying as a misallocation of intelligence in the mid-1970s.

Adlard's Multiface occupies a third position: it imagines electric autonomous vehicles as the normalized transport of a stratified future society, with hiring charges calibrated to social class and the vehicles themselves ranging from "a rectangular black box with a wheel at each corner" to glittering silver shapes that cost two months of increments for a single one-way trip. The auto in Multiface isn't aspirational — it's bureaucratic, class-marked, and slightly intimidating. The autocomplex between sectors has a map so complex that the protagonist can't parse it. This is arguably the most accurate single image in the corpus: the EV as a commodity stratified by price, the autonomous routing as a system that works but that ordinary people navigate with anxiety.

[O'Neill, The High Frontier, 1977] contributes the utopian engineering pole. His transportation thinking is genuinely inventive — maglev in vacuum predates any working maglev system, and his instinct that computer control could eliminate timetable dependency anticipates demand-responsive transit by decades. But the vision requires orbital infrastructure as a prerequisite. Everything elegant about his transport system is downstream of having already solved the hard problem of leaving Earth. This is the core limitation: O'Neill gets the technology right and the location wrong.

[Weizenbaum, Computer Power and Human Reason, 1976] contributes the critical diagnostic. His observation that computers were used to automate automobile option proliferation rather than to enable transit alternatives isn't speculative — it's a 1976 reading of a 1960s trend that has continued unbroken to the present. The 2025 automobile market, with its thousands of configurable options and its persistent underfunding of intercity rail, is the world Weizenbaum was describing, not predicting.

[Adlard, Multiface, 1975] contributes the social texture that neither O'Neill nor Weizenbaum provides. The electric vehicle as a class artifact, the autonomous routing as bureaucratic infrastructure, the protagonist studying a driving manual because the system is legible in documentation but bewildering in practice — this is recognizably the world of Uber, Tesla, and the Waymo app. Adlard even gets the gender of the vehicle right: his character instinctively assigns the car a feminine pronoun, establishing "a new and complex relationship" between man and machine. That's a 1975 observation about human-vehicle intimacy that sounds like it belongs in a 2020 think piece about people naming their Teslas.

[Clarke, The View from Serendip, 1977] contributes a sideways angle: his argument that improved communications would reduce commuting — "men do much less commuting, much more communicating" — is the prediction that half-came-true. Remote work in 2025 is real, but it didn't kill cities or eliminate commuting. Clarke's error was assuming the substitution would be clean. What actually happened is that communications technology enabled both more remote work and more distributed living that generates longer commutes for those who do travel. His mobile autonomous house — carried by sky crane, migrating south for winter — didn't happen, but the underlying impulse (decoupling residence from fixed geography) has a partial 2025 analogue in remote-work-enabled relocation patterns.

The arc across these texts runs from transportation as an engineering problem (O'Neill) to transportation as a political economy problem (Weizenbaum) to transportation as a social stratification system (Adlard). That's not a progression in publication date — all three are within a two-year window — it's a progression in analytical register. What the corpus collectively couldn't imagine was the specific synthesis that 2025 produced: electric vehicles that are technologically sophisticated (O'Neill's intuition vindicated), deployed in a market that amplifies inequality (Adlard's intuition vindicated), subsidized by computational infrastructure that deepens car dependency rather than transcending it (Weizenbaum's intuition vindicated). The three predictions aren't in tension. They're all operating simultaneously.

The one thing none of these texts anticipated was the rideshare platform as the dominant innovation in personal transportation. O'Neill imagined computer-controlled vehicles; Adlard imagined hired electric autos; Weizenbaum imagined computers misapplied to car production. None of them imagined the specific configuration of smartphone + GPS + gig labor + surge pricing that defines how a significant fraction of 2025 urban transportation actually works. The platform economy was outside the frame entirely.

This corpus is almost entirely male, Western, and engineering-oriented in its transportation imagination. The person navigating public transit with a stroller, the informal transport networks of the Global South, the cycling infrastructure debates in European cities — none of this registers. O'Neill's space habitats are imagined with bicycle paths, but as a charming detail, not as a primary mode. The pedestrian and the cyclist are absent from the serious transportation thinking here.

More significantly: the corpus treats transportation as a technical and economic question and almost never as a bodily one. Who gets tired? Who gets harassed? Whose body is assumed by the vehicle's design? Adlard comes closest — his protagonist is physically uncomfortable in the vehicle, squeezed into the seat — but even this is framed as comedy rather than as a systematic observation about who transport systems are built for. The 2025 reality of transportation access as a disability-rights issue, a gender-safety issue, and a racial-equity issue is entirely outside this telescope's field of view.

The retrieved passages also skew heavily toward O'Neill and Clarke, which means the corpus is weighted toward optimism about technical solutions. A different slice — more dystopian fiction from the same period, or more social-science adjacent writing — would likely surface the Weizenbaum register more consistently.