Henry Cavendish (1731-1810). The cleaner case, in the sense that the behaviors are so thoroughly documented and so unambiguously autistic that a formal diagnostic assessment can be done on the biographical record alone. The assessment was done: in 2009, Ioan James published a paper in Personality and Individual Differences applying Christopher Gillberg's diagnostic criteria for Asperger syndrome to Cavendish's documented behavior. The paper concludes what the biographical record already suggests. Cavendish was autistic, and the specific way in which he was autistic shaped everything about what he discovered and what he failed to share.
The documentation is dense because Cavendish was surrounded by people who kept notes. He was a member of the Royal Society. He attended meetings. Colleagues wrote letters about him. Henry Brougham, who would later become Lord Chancellor of Great Britain, left extensive descriptions of Cavendish's behavior at Royal Society dinners: that Cavendish communicated with his servants exclusively by written note left on the hall table, that he ordered his female servants to stay out of his sight on pain of immediate dismissal, that he could not hold a conversation in which more than one other person spoke, and that if approached directly at a dinner he would produce "a shrill cry" and "hasten to another part of the room." These are not the behaviors of a man who had been told he should be more friendly and was choosing not to comply. These are the behaviors of a man whose sensory and social architecture had a specific shape, and who had organized his entire life around operating within that shape.
He inherited the largest private fortune in eighteenth-century England and spent almost none of it. When his banker visited him to report that his cash balance had grown to what would today be tens of millions of pounds sitting in an unused account, Cavendish reportedly told the banker: "If it is any trouble to you, I will take it out of your hands. Do not come here to plague me!" The banker left. The money continued to accumulate. What would have been obvious to the integration specialty — that wealth is a tool, that it creates options, that it deserves attention — was invisible to Cavendish's cognitive mode, because the wealth was not a question, and Cavendish only paid attention to questions. The questions were all in the laboratory.
Cavendish measured the density of the Earth. The experiment — now called the Cavendish experiment — used a torsion balance so sensitive that he had to observe it through a telescope from an adjacent room, because his own body heat would have disturbed the measurement. He computed a value for the Earth's mean density that was within 1 percent of the modern accepted value. The experiment's conceptual difficulty was enormous. Its execution difficulty was worse. Cavendish built the apparatus himself, ran the experiment himself, and computed the result himself, across multiple years of sustained attention. He was sixty-seven years old when he published the result. He discovered hydrogen. He called it "inflammable air" and demonstrated that it burned in ordinary air to produce water — establishing, a century before it was widely understood, that water is a compound rather than an element. He quantified the gravitational constant. He anticipated Ohm's law, Dalton's law of partial pressures, Richter's law of reciprocal proportions, the concept of electrical potential, and a significant portion of what would become nineteenth-century electromagnetic theory. He wrote almost none of it down for publication.
In 1879 — seventy years after Cavendish's death — James Clerk Maxwell, by then Cavendish Professor of Experimental Physics at Cambridge, was given access to Cavendish's scientific manuscripts. What Maxwell found astonished him. In his own words, the papers showed that Cavendish had "anticipated all those leading facts in electrical science which have since been made the foundations of its mathematical theory." Cavendish had done, alone and unpublished, work that multiple subsequent physicists had independently rediscovered and published decades after his death. The rediscoverers had gotten the credit. Maxwell edited the manuscripts, annotated them, and published them as The Electrical Researches of the Honourable Henry Cavendish. The volume appeared in 1879, seventy years after Cavendish's death and roughly a century after the earliest of the recorded experiments. It is one of the clearest examples in the history of science of what the integration specialty does that the discovery specialty cannot. Without Maxwell, most of what Cavendish had discovered would have remained unknown.