Norbert Wiener and the Age of Controls, Communications, and Cybernetics—Animal and Machine—in Electrical Engineering [History]

Electrical engineers study dynamical systems, which evolve throughout time in a deterministic way. Most often, they are modeled based on the laws of physics, chemistry, science, mathematics, and economics; however, it is possible to model on previous data or heuristic rules. Engineering and technology is about comprehension and understanding. We want to know the flow of electricity, motion of a car, what keeps an airplane flying, how electrochemistry in a battery works, how hydrogen goes through a membrane in a fuel cell to produce electricity and heat, and so on. We also want to know about the balance of systems as well, how a population of wolves would stabilize an ecosystem, how goods and prices are related in an economy based on inflation, how ballast and air pressure would keep a submarine under water, and so on. The concept of feedback for single-input, single-output (SIMO) or multiple-input, multiple-output (MIMO) problems were front and center throughout the 20th century. After closed-loop control and stability were approached, there was an enhancement of understanding biological processes, medicine, psychology, social sciences, even agriculture, farming, and many other fields. The level of glucose in humans is now understood by medical doctors as negative feedback: when the glucose level is high, the pancreas releases insulin to make the sugar level in the blood decrease. And health-care providers evaluate equilibrium in several blood test data analyses to understand how substances in the blood, such as oxygen, calcium, sodium, potassium, and the number of red and white cells, are related to blood pressure, heart beats, and pupil dilation and how breathing is interrelated in the homeostasis and equilibrium of life conditions. Negative feedback has become the way to evaluate. Any positive feedback may indicate problems, requiring the short- or long-term need for interventions, precautions, and avoiding collapse situations for humans, machines, processes, and nuclear power plants.