For centuries, people have connected machines to hidden forces, to spirits, and to the divine. Some were students of magic, mediums who claimed to speak with the dead, and founders of spiritual movements. Others were the engineers and mathematicians who built the machines, who described their own work in the language of creation, miracle, and magic. What they wrote survives in patents, court records, letters, and printed books.

A few patterns recur across it.

One is the record of machines that seemed to work only for a particular person. Over several centuries, inventors and investigators saw the same thing again and again: a machine that worked only when one particular person operated it and stopped when anyone else tried, that could not be transferred to a new operator, and that never ran again after that person died. Each time, careful observers confirmed that the machine depended on the person. Each time, they divided over what that meant. Some believed the man had been operating the device secretly himself; others believed the machine drew on some power in him that no one else had. The obvious test, taking the person away to see whether the machine still runs, could not settle the question, because both explanations predict the same result: without the person, the machine stops. The machines of today are built the opposite way: they are designed to work for anyone, not for one person alone.

A second pattern is about the danger of the new powers that technology brings. More than a century ago, some spiritual teachers warned that these powers arrive before people are ready to use them well, and that they should be kept back until they are. They saw the danger not in the machine but in its owners, in whether people could be trusted with it at all. The same warning is heard now, in nearly the same terms, about advanced computing, mostly from people who have never read its earlier forms.

A third is the two opposed ways people have understood the machine itself. In one, it is a made thing that imitates life and might escape its maker’s control. This is the fear behind the old tales of artificial servants, and behind the modern worry that the machines we are now building will not stay under human control. In the other, it is neither friend nor enemy in itself, but something a capable person can take up and put to good use. In both cases the strongest version of each view came not from outsiders but from the people who built the machines.

A fourth pattern is the difference between what actually happened and the legends that formed later. People tell dramatic stories about famous inventors. One is said to have worked in secret with hidden powers, another to have built a machine to reach the dead. Some of these stories are true, and come from the inventor’s own writing. Others were invented by people who needed the past to support a belief. Telling the two apart is not always easy.

The machines now being built, the ones that can write and answer like a person, raise every one of these questions again. The questions are not new. Older versions of them appear all through this record.