Norbert Wiener was born November 26, 1894 in Columbia, Missouri.  His father was a professor of Slavic languages who wanted more than anything for his son to be a genius.  Fortunately, Norbert was up to the task.  He was reading by age three, started high school at nine, graduated at 11, got his bachelors at 14, and his masters -- from Harvard! -- at 17.  He received his PhD a year later, in 1913, with a dissertation on mathematical logic.

(If it is any consolation, Norbert was near-sighted, very nervous, clumsy, insecure, and socially inept.  However, people liked him anyway!)

After graduation, he went to Cambridge to study under Bertrand Russell, and then to the University of Gottingen to study under the famous mathematician David Hilbert.  When he returned, he taught at Columbia, Harvard, and Maine University, spent a year as a staff writer for the Encyclopedia Americana, another year as a journalist for the Boston Herald, and (though a pacifist) worked as a mathematician for the army.

Finally, in 1919, he became a professor of mathematics at MIT, where he would stay put until 1960. He married Margaret Engemann in 1926, and they had two daughters.

He began by studying the movement of particles and quantum physics, which led him to develop an interest in information transmission and control mechanisms.  While working on the latter, he coined the term cybernetics, from the Greek word for steersman, to refer to any system that has built-in correction mechanisms, i.e. is self-steering.  Appropriately, he worked on control mechanisms for the military during World War II.

In 1948, he published Cybernetics: or Control and Communication in the Animal and the Machine.  In this book, he popularized such terms as input, output, and feedback!

Later, in 1964, he published the book God and Golem, Inc., which he subtitled “a comment on certain points where cybernetics impinges on religion.”  He was concerned that someday machines may overtake us, their creators.  That same year, he won the National Medal of Science.  A few weeks later, March 18, he died in Stockholm, Sweden.

The idea of feedback is very old, and is hinted at in the works of Aristotle.  It began to gain some notoriety in the 1700's, in the form of "the invisible hand," an idea introduced in Adam Smith's The Wealth of Nations, which some see as the roots of both control theory and game theory.  Feedback is a simple idea:  Take the output of some system, and feed it back as an input, in order to in some way alter the process.  For example, homeostasis or the thermostat principle is a form of negative feedback:  It gets cold in the house, which triggers the thermostat, which turns on the furnace.  It gets warmer, which triggers the thermostat, this time to turn off the furnace.  Then, it gets colder, and the cycle begins again.  The goal of such a system is equilibrium (say, 70º F in the house), but it is actually an oscillating or "hunting" process.

Positive feedback occurs when the output tells the system to produce even more of something.  Although the "positive" in positive feedback makes it sound like a good thing, if it isn't backed up with negative feedback, it tends to run out of control.  A common example of positive feedback are economic bubbles, where something increases in value (such as tulips in 17th century Holland, or "dot-coms" in the recent past), everyone buys into the product, driving up the prices, leading to more investors, until finally the whole thing collapses.

What Wiener did was recognize the larger significance of this feedback idea!