Thinking about Machines and Thinking

By David C. Brock | January 28, 2021

In Paris. Exactly Seventy Years Ago.

He likely arrived in Paris from Darmstadt, Germany, by train that January, exactly seventy years ago. At 53, and a full professor of applied mathematics and the founding director of the Institut für Praktische Mathematik at the Technische Hochschule Darmstadt, Alwin Walther was among Germany’s leading figures in computation. The calculational prowess of Walther and his Institut–employing all manner of manual, mechanical, and electromechanical approaches–had attracted the attention, and the support, of the Nazi regime during the Second World War. But as Walther made his way to the academic heart of liberated Paris, the Latin Quarter, few passersby would have guessed at this background.

Alwin Walther in 1964. Credit: By GFHund—Own work, CC BY 3.0/Wikimedia Commons

Walther’s Institut had been a major source of the calculational support needed for Werner von Braun’s rocketry efforts, most notably the V-2, for the Germany Army. Indeed, during the war, Walther secured funding from the German Army to create an advanced electromechanical analog computer: an advanced differential analyzer to rival that created earlier by Vannevar Bush at MIT. (The system, the IPM-Ott DGM, was developed throughout the war, but only delivered to Walther’s Institut in 1948.) This work with von Braun and the German Army was not the only effort that connected Alwin Walther with slave labor, like that from German concentration camps exploited in the V-2 rocket factories. More directly, Walther was evidently involved in a scheme with the Nazi SS to enslave Jewish scientists held in the Sachsenhausen concentration camp to perform manual calculations. If the scheme actually had been put in place, which is unclear, it was soon upended, along with the other activities of Walther’s Institut, when its facilities, the vast majority of the buildings of the Technische Hochschule Darmstadt, and much of the rest of the city were destroyed during Allied air raids on September 11 and 12, 1944.1

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Darmstadt after the air raids of September 1944. Credit: U.S. Air Force, Public domain/Wikimedia Commons

In new facilities created after the war, Walther and his Institut had their eyes firmly set on electronic digital computing. During the war, members of the Institut and its machine shop had provided direct support for Konrad Zuse’s famed electromechanical Z4 computer. (The Z4 was a pioneering digital computer, originally intended for use in the German aircraft industry. To learn more about it, see Walther himself developed wartime plans for a large electromechanical computer along the lines of Howard Aiken’s Mark 1, but those were abandoned. As Walther packed his belongings for his January 1951 trip to Paris, he and his Institut had just embarked on a major new effort to create a stored-program, electronic digital computer. This machine, the Darmstädter Elektronischer Rechenautomat, or DERA, became operational in 1957, a decade before Walther’s death.2

Walther demonstrating the DERA in 1963.

Surely, Walther must have had with him in Paris a particular bundle of papers. These were his copies of the announcement, printed schedule, registrant list, and both French and English sets of presentation abstracts for the international conference he was attending in Paris from the afternoon of Monday, January 8th, 1951 through the afternoon of Saturday, the 13th. The conference was organized by the five-year-old Institut Blaise Pascal, the computing center of the French scientific and engineering research establishment, the Centre National de la Research Scientifique (CNRS). The French Institut was composed of two laboratories, one devoted to analog computation and the other, led by Louis Couffignal, for digital computation. It was Couffignal who was the principal figure behind the January 1951 international conference.3

Couffignal (left) with Howard Aiken at this conference. Credit: The Tomash Library on the History of Computing, hosted by the Charles Babbage Institute

Couffignal had completed a doctorate in mathematics on the theory of computation at the University of Paris in 1938, with the ambition to create a new binary-based calculating machine. During the war-time occupation of the city by the Germans, Couffignal had met intensely and often with perhaps France’s leading physiologist, Louis Lapicque. Lapicque, famed for his integrate-and-fire model of the neuron, and Couffignal found a common vision, seeing deep analogies and connections between the processes and physiology of human thought and the processes and componentry of calculating machines. Imprisoned by the German Gestapo for aiding the resistance, Lapicque nevertheless managed to write his book La Machine Nerveuse, which was published in 1943. In it, Lapicque gave voice to this vision shared with Couffignal: “. . . the regular periodic organization of cerebellar elements made cerebellum close to artificial machines. Some of its processes may be understood by comparison with calculating machine or automatic telephone relays.”4 Like many who came before them, Couffignal and Lapicque were using human-made tools of great current fascination as analogical tools for understanding human bodies and minds. Where earlier thinkers had been entranced with clockworks, seeing themselves in the gears and windings, these Couffignal, Lapicque and others of the 1940s looked at electromechanical and electronic calculating machines, and saw human bodies and minds mirrored therein.

Louis Lapicque, 1920. Credit: US National Library of Medicine.

Working for the CNRS during the war positioned Couffignal to take up leadership of the digital computing laboratory of the Institut Blaise Pascal in 1946, initially only equipped with desktop electromechanical calculators confiscated from the Germans, but fired with ambition to make a new, French, binary computer. In the first year of his new directorship, Couffignal traveled to the United States to deepen his understanding of American developments in both electronic computing and the computing-view of human thinking. In Philadelphia, he familiarized himself with ENIAC. (ENIAC was a newly completed, all-electronic digital computer, and a milestone in the history of computing. Learn more.) In Princeton, Couffignal learned about the development of the Institute for Advanced Study (IAS) computer by John von Neumann. (The IAS computer was a “stored program” machine, holding both software and data in its memory. The power of this approach made the IAS computer a model for many early digital computers around the world. (Learn more.) At Harvard Couffignal visited Howard Aiken and saw his electromechanical computers. (Learn more.) But it was in Cambridge that Couffignal found the chance to pursue his interest in what we might call the “computing-view of human thought,” meeting with the mathematician Norbert Wiener at MIT. Deep into the work that would lead him to publish his book Cybernetics in 1948, Wiener evidently found a kindred spirit in Couffignal. In 1947, he returned the visit, meeting with Couffignal and Lapicque in Paris.5

Norbert Wiener. Credit: MIT Museum.

The same sort of analogic thinking that for Couffignal, Lapicque, and Wiener led them to see bodies and minds like servo-mechanisms (an automatic control based on feedback), electromechanical relays, and electronic circuits had, by 1951, also led Couffignal to head France’s main effort to develop a large scale digital electronic computer in a very particular direction. As early as his 1938 doctoral thesis, Couffignal was already engaged in analogic thinking about calculating machines that connected with physiology. He wrote, “To give a full account of the development (of calculating machines) we must create for machinery the analogues of comparative anatomy and physiology.” What Couffignal concluded, in short, was that this physiology of calculating machines displayed an evolution in which increased calculating power was achieved by increasing complexity. In 1947, when Couffignal had control of France’s major effort to build a large-scale digital computer, his evolutionary conclusion of 1938 now carried real weight. France’s computer would depart from the designs he saw in America, which in his “comparative anatomy” of computer design embraced a simplicity of calculation logic, thereby emphasizing the need for large memories. This was, for Couffignal, a kind of devolution, a reversion against complexity and therefore progress. France’s computer, in contrast, would embrace large, parallel, units of complex calculating logic, and minimize, even eliminate, memory. In this, Couffignal explained, “the problem of organizing a calculation is essentially the same as that of organizing a factory assembly line."6

Couffignal’s pilot-machine. Credit: History Computer.

By January 1951, a “pilot-machine” embodying Couffignal’s strikingly different approach to electronic digital computing was in operation within his laboratory of the Institut Blaise Pascal. It was the result of four years of efforts by the principal contractor, the Logabax Company, and the expenditure of millions of francs by the CNRS. Whatever else one might say of it, it could actually compute, able to calculate square roots and sine functions. Through the auspices of the CNRS, and with some additional funding from the Rockefeller Foundation, and with his pilot-machine ready to demonstrate, Couffignal organized an ambitious international conference that combined his two greatest passions: large scale digital electronic computers and the computation-view of human thought. It gathered together some of the leading lights of digital computer development from across the world, as well as an international coterie of researchers inspired by the view of the mind as a machine. After 1948, when Wiener’s book spun the term into circulation, this later group would be known as devotees of cybernetics.7

The view down Rue d’Ulm, toward the Panthéon. Credit: Guilhem Vellut from Paris, France, CC BY 2.0/Wikimedia Commons.

The conference was titled “Les Machines a Calculer et la Pensée Humaine” (Computing Machines and Human Thought) and was held in the meeting rooms of the Centre National de Documentation Pédagogique—the French state’s educational publishing arm—located just a three-minute stroll from Couffignal’s laboratory in the Institut Henri Pointcaré, around the corner at 29 Rue d’Ulm. A distributed “Liste Alphabetique des Membres du Colloque” presented a roster of attendees, along with their affiliations.

The roster at some point became data for Alwin Walther to analyze, perhaps on his way from Darmstadt to Paris. Pencil in hand, he annotated each page of the “Liste,” counting the distribution of attendees by country. What motivated his survey of the conference’s geographic diversity is unclear, but what is undoubted is that he noted that he was the single German to attend. He was the “1 Allemande,” he scribbled in his final count: 5 from the USA; 184 from France; 40 from the UK; 5 from Spain; 8 from the Netherlands; 6 from Belgium; 4 from Italy; 4 from Sweden; 1 from Switzerland; 1 from Germany; and 1 from Brazil. The 259 attendees were occupationally diverse as well, hailing from universities, telecommunications firms, medical institutions, military organizations, computer manufacturers, academic and professional societies, journalism, diplomacy, industry, the UN, and museums.

Walther’s annotated list. Credit: CHM Collection, 102805935

The six days of the conference were broken into three two-day parts. The opening part focused on “Progrès Récents dans la Techique des Grosses Machines a Calculer,” new developments in the approach to large scale digital computers. Quantum physics pioneer, Nobel Laureate, and Secretary of the Academie des Sciences, Louis de Broglie, delivered the opening welcome and was followed by a series of presentations on the latest electronic digital computers. Harvard’s Howard Aiken spoke about his Mark II, III, and IV machines. Birkbeck College’s Andrew Booth described his experimental SEC and his new APEXC computer. Eduard Stiefel, head of applied mathematics at the ETH Zurich, spoke of Konrad Zuse’s Z4 computer, now under Stiefel’s care. E.W. Cannon, a leader for mathematics at the National Bureau of Standards, surveyed the organization’s history with computing, including SEAC and SWAC. F.C. Colebrook of the National Physical Laboratory described its recent success with the Pilot ACE computer, originally designed by Alan Turing. At the close of the first day, Couffignal demonstrated his laboratory’s pilot-machine to the conferees, it’s world debut. The second day continued with presentations about additional new computing work, such as Freddie Williams’ review of computer work at the University of Manchester, and discussions of various digital and analog computing approaches.


Howard Aiken. Credit: CHM Collection, 102635870

The middle part of the conference was devoted to the kinds of mathematical and scientific problems that were appropriate applications for the large-scale digital computers reviewed in the conference’s first part. Linear and differential equations made numerous appearances. Douglas Hartree and Maurice Wilkes both spoke about their experiences programming the University of Cambridge’s new EDSAC computer.


Maurice Wilkes holding a part of the EDSAC. Credit: CHM Collection, 102630805

For the concluding part of the conference, Couffignal turned to the colleague with whom he had perhaps most discussed the vision of the mind as machine: Louis Lapicque. The final topic was “Les Grosses Machines, La Logique et la Physiologie du Système Nerveux,” large digital computers and the logic and physiology of the nervous system. The morning of Friday, January 12, 1951 was dominated by a presentation about Leonardo Torres y Quevedo, and demonstrations of a set of devices he had made. Torres y Quevedo, a wildly inventive and celebrated Spanish engineer, was born in 1852 and had died in 1936.8 He had been, as well, a kind of intellectual companion to Coffignal’s dissertation advisor and mentor, Maurice d’Ocagne.9 At Couffignal’s conference, Torres y Quevedo’s son Gonzalo introduced or reacquainted this elite international audience to his father’s works. Torres y Quevedo embraced a vision of what his son called “automism,” the possibility for creating ever more sophisticated autonomous machinery which could encompass actions and behaviors previously the sole domain of humans. On exhibit for the 1951 conferees was an electromagnetic chess playing machine from the 1920s, a system called “Telekino” utilizing radio waves and servo-mechanisms for the remote guidance of boats, and a complex mechanical device called the “endless spindle” for calculating logarithms.

Gonzalo Torres y Quevedo, Norbert Wiener, and the chess machine at the 1951 conference. Credit: CHM Collection, 102645396

Following Torres y Quevedo’s morning presentation, the afternoon was given over to names that would, in time, become indelibly liked to cybernetics. Ross Ashby, a British psychiatrist and researcher, presented his subsequently famous “Homeostat,” an electronic system designed to adapt to it environment, and described in his 1948 paper, “Design for a Brain.” Ashby was followed by Grey Walter, a British neurophysiologist, who demonstrated his own subsequently famous light-sensitive robot “tortoises.”10 None other than Norbert Wiener himself followed, with a rather remarkable talk in which he speculated about the possibilities for computing machines to afford humanity new kinds of sensory perceptions of form, “gestalt,” “. . . which are not in our nervous system.” New realms of perception might be opened to a new kind of body combining mind and machine.

Grey Walter demonstrates a “tortoise” in 1952. Credit: ResearchGate

Other speakers that Friday afternoon included Albert Uttley, a researcher at the UK’s National Physical Laboratory and central figure in the Ratio Club, a dining club of British cyberneticists that met in the basement of a London neurological hospital.11 Appearing also was the Chicago neurophysiologist Warren McCulloch, who with the astonishing talent of Walter Pitts had pioneered the concept of “nervous nets”¬—our “neural nets”—in 1943, with ideas for using such nets to perform logic and other calculations.12 At the Paris conference, he quipped “Brains are calculating machines, but man-made calculating machines are not yet brains.”

If the notion of McCulloch and Pitts was the creation of machines on the model of minds—well, at least brains—the closing remarks for the entire conference marched in a contrary direction. The final speech fell, surely by design, to Couffignal himself. Late in the morning of Saturday, January 13, he spoke of “Several New Analogies Between the Structures of Calculating Machines and Brain Structures.” Taking the brain to be “a machine where thoughts are elaborated and the [sic] logic as the working-method of that apparatus,” he proposed that a body of knowledge could be constructed about the actual “working processes” of the brain and that these actualities could be directly compared to the “ideal logic performed with computing machines.” The result? Not McCulloch and Pitts effort to make new machines act more like brains, but rather to make minds more like existing computers. Couffignal’s aim was not to make computers think like humans, but for humans to think like computers. Why? He believed it would be good for people: “On individual scale, an enlargement of social strength of intelligence can be expected,” perhaps by breaking through the “few steady ideas” inherited by our “civilization” with which Couffignal thought humans based our actual reasoning. He concluded, “. . . and, on human scale, an encreasement of the intellectual potential [sic].” Together, by thinking like computers, humanity would create a new and improved version of itself.

While Couffignal dreamt of reasoning more like a computer, he assuredly practiced eating like a Parisian. After his conclusion to the conference, the conferees made their way across the city to the 17th Arrondissement, and the Ecole Hotelière. Opened in the 1930s, the school trained hundreds of aspiring Parisian hotel chefs. One of its restaurants boasted a replica of a dining room aboard the luxury ocean liner SS Normandie.13 The 1951 conference’s “Banquet de Cloture” was no doubt delicious, but the announcement of it showed the dyspeptic truth that only men had attended the conference proper. Any women who accompanied them, however, were invited to the banquet: “Les dames accompagnato les members du Colloque sont admises au banquet.”

After this remarkable conference, Couffignal’s career did not rise to greater heights. The Logabax Company, which was finishing work on Couffignal’s pilot-machine and had started on his ambitious, memory-minimizing, parallel-design large computer, went bankrupt in 1952 and closed. Couffignal’s large machine remained forever unbuilt. He and his laboratory struggled along, eventually buying an Elliott 402 computer: A rather standard, vacuum-tube, stored-program computer with a magnetic drum memory. For Couffignal, the purchase must have felt, at least somewhere within him, like humiliation. The Elliott was the epitome of everything his unbuilt design was not. In 1959, he was fired. Through a series of books published in the 1950s and 1960s on cybernetics, Couffignal earned himself a twin legacy: Today, he is generally seen as having given French digital computer manufacture something of an initial disadvantage, while at the same time he is included as an important early figure within French cybernetics.14

The Elliott 402 Computer. Credit: Chilton Computing

Alwin Walther, for his part, left Paris and returned to Darmstadt, where he continued the physical reconstruction and technological evolution of his Institut für Praktische Mathematik. Among other efforts, he began his own effort to create an electronic digital computer. It would take him until the end of the decade, but he succeeded in creating a vaccum tube-based machine for his Institut, the DERA.15 Walther must also have found his Parisian experience to have been of great value, for in 1955 he and his Institut organized and hosted their own large international conference on digital computing. Less fleetingly, he built up a considerable library of the available literature on computing at his Institut, making it into a key resource for the developing German computing community.16

For this library, Walther had bound together the various documents he had brought home with him from Couffignal’s 1951 Paris conference: the four-page printed program; the three-page typescript conference announcement; the nine-page list of attendees; and over 100 pages of abstracts for the presentations, both in English and in French. This bound volume sat on the shelves of the Institut’s library as item number B8807 for years.

As for the others in attendance at Couffignal’s 1951 conference, their full comments were presented in French in a publication by the CNRS in 1953, under the same title as the conference. Running to over 560 pages, this record ironically remains—at least by an ardent search by this author—inaccessible freely on the web. Nevertheless, many of the attendees have become the perennial subjects of the history of science and technology, especially computing.

With time, Walther’s bound volume of his 1951 conference materials were deaccessioned by his Instiut’s library. From there, the volume attracted the discerning eye of Jeremy Norman, a noted collector and dealer in rare books and manuscripts in the history of science and technology. Norman, in turn, used the volume in his and Diana Hook’s 2002 documentary history, The Origins of Cyberspace: A Library on the History of Computing, Networking, and Telecommunications. More recently, Jeremy Norman included Walther’s bound volume in a lot of rare books he donated to the collection of the Computer History Museum. The volume now resides in the Museum’s archival facility in the San Francisco Bay Area, while a new PDF scan of it resides in a Microsoft computer somewhere in the Azure infrastructure, and might reside on your computer or phone should you download it here

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Les machines a calculer et la pensee humaine

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How in the end, should we think about Couffignal’s 1951 conference? What do we make of it? The computer scientist turned computing historian Herbert Bruderer considers if the conference marked the “birthplace of artificial intelligence,” rather than the more famous Dartmouth Conference of 1956. In a 2017 piece, he writes “this well-documented event could also be regarded as the first major conference of artificial intelligence.”17 This view hinges on just how one takes the phrase “artificial intelligence.” My own perspective is that the 1951 conference was certainly part of the building of a community: a community of people thinking about and building computers and cybernetic machines. It was a community animated by thinking about minds and machines together, also considering—some even pursuing—machines as minds. In this, the conference is evidence of the long story of what we could today call “artificial intelligence” and how it weaves throughout computer history. Download the PDF of Walther’s bound papers and see what you think.

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Artificial Intelligence at CHM

For decades, CHM has been collecting materials to preserve and interpret the history of artificial intelligence (AI), providing the foundation to put the present in context and understand the digital future of humanity. Explore highlights from the collection.

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  1.; Wilfred de Beauclair, “Alwin Walther, IPM, and the Development of Calculator/Computer Technology in Germany, 1930-1945,” Annals of the History of Computing, v. 8, n.4, October 1986, pp. 334-350.
  2. De Beauclair;
  3. Girolamo Ramunni, “Louis Couffignal, 1902-1966: Informatics Pioneer in France?” Annals of the History of Computing, v. 11, n. 4, 1989, pp. 247-256; Pierre E. Mournier-Kuhn, “The Instiut Blaise-Pascal (1946-1969) from Couffignal’s Machine to Artificial Intelligence,” Annals of the History of Computing, v.11, n.4, 1989, pp. 257-261;;;
  6. Ramunni.
  7. Mounier-Kuhn;
  9. Ramunni.
  10.   See Andy Pickering, The Cybernetic Brain: Sketches of Another Future, University of Chicago Press, 2009.
  14.   Ramunni and Mournier Kuhn.
  15.   Herbert Bruderer, Milestones in Analog and Digital Computing, Third Edition, Springer, 2020.
  16.   De Beauclair.

About The Author

David C. Brock is an historian of technology, CHM's Director of Curatorial Affairs, and director of its Software History Center. He focuses on histories of computing and semiconductors as well as on oral history. He is the co-author of Moore’s Law: The Life of Gordon Moore, Silicon Valley’s Quiet Revolutionary and is on Twitter @dcbrock.

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