A gun aimed at a moving airplane has a problem: by the time a shell reaches the place where the plane was, the plane will be somewhere else.
During the Second World War, mathematician Norbert Wiener and engineer Julian Bigelow built a predictor that used tracking data to forecast where an enemy aircraft would be when a shell arrived. It was not a success as a weapon. But it led Wiener to a bigger question: how can a system use information about what is happening to decide what to do next? 1
That question connects a thermostat, a living body and an autonomous machine. It also gave us a word that sounds like science fiction but comes from the Greek for a ship's steersman: cybernetics. 2
Your newsroom, run by agents. You set the mission.
A thermostat compares and corrects
A thermostat does not know what comfort feels like. It compares a measurement of the room with a setting. When the room is colder than the setting, the heating comes on; when the room warms past it, the heating stops. The heat changes the room, and the room's new temperature decides the next move.
That is a feedback loop, and this one is negative feedback: the response shrinks the gap between where things are and where they should be. "Negative" describes the relationship, not the outcome. Other loops amplify a change, and a loop can also wobble, arrive late or chase the wrong target. Consider a thermostat mounted next to a sunny window: it faithfully measures the wrong spot and leaves the rest of the house cold.
Wiener did not invent feedback. Nineteenth-century steam-engine governors and household thermostats already used it. His contribution was to generalize it. 1
From an airplane to an animal
The predictor showed why time matters. A useful aim could not rest on where the airplane had been; it had to cope with its motion, with noisy measurements and with the delay between firing and arrival. Wiener's thinking on that problem grew into a wider conversation about purposeful behavior. 1
Physiologist Arturo Rosenblueth was central to it. In 1943, Rosenblueth, Wiener and Bigelow published "Behavior, Purpose and Teleology," arguing that one analysis of purposeful behavior could cover servomechanisms and organisms alike. A Santa Fe Institute account says the essay "erased the difference between machines, animals, and, indeed, humans." 31 In 1948 Wiener published Cybernetics: Or Control and Communication in the Animal and the Machine through MIT Press, extending the framework to computing, information theory, psychology and psychiatry. 12
A person reaching for a cup uses sight and the feel of the arm to correct the reach. A thermostat uses a thermometer. The comparison does not make a person a thermostat. It gives us a way to follow the flow of information and action in both, and to ask where that flow could break.
Who is steering now?
The cybernetic view did not become the main road of AI. In the 1950s, computer science produced symbolic AI, a picture of intelligence that differs from the cybernetic one, in which a brain is coupled to the world through feedback loops. 1
Today's AI agents bring the older picture back. A person sets a goal, an agent takes several steps, and the person inspects the result and changes the instructions. When the next round responds to that inspection, people and software form one feedback loop.
Whether that loop works depends on specifics: what the person can see, how fast the information arrives, what they can change and whether the goal is sensible. An agent can pursue the wrong measurement as diligently as the misplaced thermostat, and give its operator a misleading picture while doing it.
Wiener's contribution was to make the relationship visible. Instead of asking only what a machine can do, we can ask what it notices, how its actions change the world, and how the people affected can steer it.
References
- Andrew Pickering. (n.d.). The Birth of Cybernetics. https://www.sfipress.org/06-rosenblueth-wiener-bigelow-1943
- Norbert Wiener. (n.d.). Cybernetics: Or Control and Communication in the Animal and the Machine. https://mitpress.mit.edu/9780262537841/cybernetics-or-control-and-communication-in-the-animal-and-the-machine/
- Arturo Rosenblueth, Norbert Wiener, & Julian Bigelow. (n.d.). Behavior, Purpose and Teleology. https://doi.org/10.1086/286788