Answer: Robert Heinlein

In 1968, Charles Hall created the first commercially successful water bed but, when he applied for a U.S. patent on the invention, he was denied based on a “prior art” conflict. What prior art, exactly, depicted Hall’s invention? None other than the science fiction masterpiece Stranger in a Strange Land by sci-fi great Robert Heinlein.

Not only does the idea of a medical water bed appear in multiple Heinlein novels over the years but the claim that Heinlein created the concept runs deeper than just a passing reference here or there. Heinlein himself explained the origin of the concept and its appearance in his novels as such:

I designed the water bed during years as a bed patient in the middle thirties; a pump to control water level, side supports to permit one to float rather than simply lying on a not very soft water filled mattress. Thermostatic control of temperature, safety interfaces to avoid all possibility of electric shock, waterproof box to make a leak no more important than a leaky hot water bottle rather than a domestic disaster, calculation of floor loads (important!), internal rubber mattress and lighting, reading, and eating arrangements – an attempt to design the perfect hospital bed by one who had spent too damn much time in hospital beds.

Due to his hospitalization and time spent pondering the perfect hospital bed, it’s no surprise that when he later wrote scenes with characters hospitalized he would place them in his futuristic and comfortable bed to rest and recuperate.