A World Without Touch
Solaria was colonized relatively late among the Spacer worlds but quickly developed the most extreme social structure. With a population deliberately maintained at exactly 20,000 humans on a planet capable of supporting billions, Solaria offered each citizen an estate of staggering proportions.
Solarians distinguished sharply between 'viewing' (holographic communication) and 'seeing' (physical presence). Viewing was routine and comfortable; seeing was deeply traumatic for most Solarians, who would experience physical revulsion at the proximity of another human being.
Elijah Baley's Investigation
In 'The Naked Sun,' Earth detective Elijah Baley was sent to Solaria to investigate the first murder in the planet's history — a crime deemed impossible in a society where humans never met in person. Working with R. Daneel Olivaw, Baley had to overcome his own agoraphobia while navigating a society that found his very presence offensive.
The investigation revealed deep cracks in Solarian society and demonstrated that extreme isolation, far from eliminating crime, simply drove it into forms that the society could not recognize or investigate.
The Sealed World
Solaria's ultimate fate is among the most haunting in Asimov's universe. By the time of 'Foundation and Earth,' the Solarians had genetically engineered themselves into hermaphrodites who could reproduce alone. They sealed their planet against outsiders and developed 'transducer' brain lobes that let each Solarian draw on the energy of their vast estate to power their robots and defend themselves.
When Trevize visited Solaria, he found a functional world still maintained by robots, but with humans that were no longer recognizably human — a species that had evolved beyond the need for society itself.