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Alonzo Church:Unsung Hero of Modern Computing


When Alonzo Church's father's poor eyesight led to removal from the D.C. bench, the young Church found himself in Virginia, far away from the fast- paced city life that he had come to know. From such beginnings, it would have been fair to doubt that this young man, then down on his luck, would go on to lay the groundwork for the computer, one of the most important inventions in all of history, the computer. This doubt, though, would have been in error.


The generosity of an uncle would help turn Church's path, affording him first a private grade-school education and then an opportunity to study at Princeton, where he excelled in mathematics. He proceeded on to his Ph.D. at Princeton, studying under Oswald Veblen, who would go on to found the Institute for Advanced Study. After graduating, Church became a professor as well.


In 1936, Church published some of his work on computing in a paper that introduced the world to lambda calculus. At the time a novel concept, lambda calculus has since evolved into a key concept among computer scientists developing new programming languages.

Simultaneous to Church's discovery of lambda calculus, Alan Turing was in the United Kingdom doing his own research into computing. There, he developed what he called the automatic machine, which would become better known as the Turing machine. This research into computability – the mathematical and logical foundation of the modern computer and all that has led from it, including artificial intelligence and machine learning – contributed to Turing's work with Bletchley Park, where he and other British cryptologists cracked the German Enigma machine, deciphering encrypted messages during World War II. Nearer to the end of the war, Turing also applied his research to the development of Colossus, a first- generation electric, digital, programmable computer.

Before that, however, Turing and Church had already crossed paths. When Church published his research on lambda calculus in 1936, Turing read it and made the trip to Princeton, where he became Church's doctoral student. Their work, both collaborative and independent, led to the Church-Turing thesis, another hallmark of computability theory.


Their lives forever intertwined, Turing and Church nonetheless spent a small portion of each of their lives together. Turing died an untimely death in 1954, while Church lived into his 90s. Namesake of the Turing machine and the Turing test, a measure of a machine's ability to imitate intelligent human behavior, Alan Turing has become the more famous of the two mathematicians, his life story the basis for the Academy Award-winning movie The Imitation Game.

Church's contributions to mathematics, philosophy, linguistics, and of course, modern computing are immense. In his honor, the Association for Computing Machinery awards the Alonzo Church Award every year, recognizing achievements in computer science logic. A prerequisite for the award is that the recipient has done the relevant work within the last 25 years and received no prior recognition for it, in the form of a major award such as the Gödel Prize, the Paris Kanellakis Award, or the Turing Award. It seems fitting that the Alonzo Church Award, named for a man whose contemporary recognition seems to fall short of his life's achievement, would focus on those of similar renown.