Licklider, Joseph Carl Robnett

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LICKLIDER, JOSEPH CARL ROBNETT

(b. St. Louis, Missouri, 11 March 1915; d. Arlington, Massachusetts, 26 June 1990),

acoustics, engineering psychology, computer science.

J.C.R. Licklider started his academic career as an experimental psychologist. His area of concern broadened from acoustics to engineering psychology and then to human-computer interaction and computerized library systems. From 1962 to 1964 Licklider served as the first director of the Information Processing Techniques Office (IPTO) of the Department of Defense’s Advanced Research Projects Agency, the largest federal funding agency of the time for the computing field. His administration of the office galvanized the emerging computer science field into shaping research agendas in time-sharing systems, artificial intelligence, computer graphics, and later, networking. The essential features of modern personal computing can be traced to his inspiration.

Family Background and Education . Licklider was the son of Joseph Parron Licklider (b. 1873) and Margarete Robnett Licklider (b. 1881) and grew up in St. Louis, Missouri. In 1937 Licklider graduated from Washington University in St. Louis, where he majored in physics, mathematics, and psychology. A year later he received a master’s degree from Washington University and in 1942 a PhD in Psychology from the University of Rochester. His dissertation topic was “An Electrical Investigation of Frequency-Localization in the Auditory Cortex of the Cat.” On 20 January 1945 he married Alberta Louise Carpenter (b. 1919); they would have two childen, Tracy Robnett (b. 1947) and Linda Louise (b. 1949).

As an Academic Psychologist . Licklider taught at Swarthmore College as a research associate in the Department of Psychology for one year while completing his PhD and in 1942 joined the Psycho-Acoustic Laboratory at Harvard University as a research associate. Mobilized during World War II, the laboratory, under the leadership of Professor Stanley Smith Stevens, contributed applied research on acoustics. Licklider concentrated on acoustic intelligibility under combat conditions. The primary area of Licklider’s research was the effect upon intelligibility of various distortions of speech; he also studied the effects of high altitude on speech communication and the effects of static on communication by radio receivers.

When the war was over, Licklider, like his colleagues, made good use of the laboratory’s accumulated knowledge and research environment; he went on to investigate inter-aural phase, binaural beats, and, in conjunction with George A. Miller, the intelligibility of interrupted speech. His publication of that research after the war earned peer recognition of his most important contribution to the acoustics area, a new formulation of the problem of pitch perception. Licklider was a guest at the seventh Macy Conference, “Cybernetics: Circular Causal and Feedback Mechanisms in Biological and Social Systems,” held on 23–24 March 1950. Licklider gave the talk “The Manner In Which and Extent To Which Speech Can Be Distorted and Remain Intelligible,” referring to his recent papers published in the Journal of the Acoustical Society of America. In the same year, Licklider received the society’s Biennial Award for Outstanding Contributions to Acoustics and moved from Harvard, where he had been lecturer in psychology since 1946, to the Massachusetts Institute of Technology’s Department of Electrical Engineering as associate professor of psychology of communications.

In the Handbook of Experimental Psychology (1951) edited by Stanley Smith Stevens, which became an essential reference in the field, Licklider contributed chapter 25, “Basic Correlates of the Auditory Stimulus,” and, with George A. Miller, chapter 26, “The Perception of Speech.” He subsequently served as the president of the Acoustical Society of America from 1958 to 1959.

A Truly SAGE System . With the advent of the Cold War, Licklider participated in various summer studies in which interdisciplinary groups of scientists and engineers sought solutions to military problems. In 1950 Project Hartwell was held at MIT to study overseas transport and undersea warfare; in 1952 Project Charles at MIT studied air defense; in 1956 a group at the University of Michigan discussed battlefield surveillance; and in 1957 and 1958 an Air Force Special Summer Study on general subjects was held at Woods Hole, Massachusetts. Project Charles led in 1954 to a project for a nationwide air defense system, subsequently called SAGE (Semi-Automatic Ground Environment). SAGE was a command and control network for air defense, designed to coordinate all air defense components at individual Direction Centers by a digital computer and a backup at each location. In tandem with Project Charles, Project Lincoln at MIT carried out experimental work on some elements of the air defense system, jointly supported by the U.S. Army, Navy, and Air Force, which led to the establishment of the MIT Lincoln Laboratory. George Miller became the official group leader of the laboratory’s psychology department. As a consultant to the group, Licklider closely collaborated with Miller on various projects in the early 1950s.

Licklider was the only psychologist who participated in Project Charles and who was exposed to its knowledge about digital computers. Having the SAGE system as a model in mind, Licklider conceived of the “Truly SAGE system or Toward a Man-Machine System for Thinking” and wrote a proposal for it to the Air Force in 1957. As Licklider wrote on the cover page, the aim of the document was “to suggest a kind of system that seems desirable and reasonable from a psychological point of view and not totally unfeasible from a psychologist’s approximation of an engineering point of view.” Following the model of SAGE, Licklider proposed a system of networked “information centers.” In each center, “there is of course a large-scale digital computer with a very extensive memory,” and “the centers for related fields are connected one with another by telecommunication channels” (p. 2).

Although SAGE as an air defense system for bombers was already out of date when it became operational in 1958 because of the intercontinental ballistic missile (ICBM), it had a great impact on military system design, computer research, and industry. Air traffic control systems and online reservation systems such as American Airlines’ SABRE were among direct applications of SAGE. As a form of computing, SAGE was an online system that handled many inputs and outputs during a process, a realtime system designed to meet the deadlines for real world demands, and a data communication system using phone lines through modems (devices that modulate-demodulate digital information into analog signals and vice versa).

Indeed, the computing style in each center of the “Truly SAGE System” would be online real-time, as was SAGE. However, it would allow simultaneous access by multiple users to share the information stored in the centers, so that the system would be based on a “time-sharing” technique, which was not yet realized in SAGE: “The computer is operated on a time-sharing basis by a number of people. The arrangements for displaying information to the people are highly developed. They include digital-analogue converters, curve plotters, large-screen cathode-ray tubes, automatic typing or printing machines, and loudspeakers.” It is notable that Licklider mentioned “time-sharing by a number of people” here: This 1957 document is one of the earliest written records mentioning “time-sharing” in this sense. It was possible that Licklider had been exposed to the phrase “time-sharing” at the SAGE project, although it was used there to describe the SAGE program’s cyclic scheduling process. The phrase “time-sharing” was used as a technical term from the mid-1950s through the 1960s with different meanings. Although the diversity of its usage even became controversial in the mid-1960s, in his 1957 document Licklider’s use of the term was clear, and thereafter he pursued the development of time-sharing techniques in his sense.

At Bolt Beranek & Newman . In 1957 Licklider left MIT to become head of the departments of psychoacoustics, engineering psychology, and information systems at Bolt Beranek & Newman Inc. (BBN) in Cambridge, Massachusetts. With little administrative support, Licklider had abandoned the effort to form a psychology section at MIT, although he had already recruited prominent young psychologists. Among them, two assistant professors, David Green and John A. Swets, joined him as part-time workers at BBN. At MIT’s Lincoln Laboratory, a group headed by Wesley Clark built TX computers that could support online conversational computing through graphical outputs on a display and through input devices such as a light pen and a keyboard. Licklider witnessed the usability of the system and had a concrete image of advanced human-computer interaction. He persuaded Leo Beranek, one of the founders of BBN, to buy a digital computer, a Royal McBee LPG-30, and learned programming with the help of Edward Fredkin. In 1959 the prototype of the Digital Equipment Corporation’s first product, PDP-1, designed after the TX computers, was brought to BBN. In a short time Licklider started working with John McCarthy and Marvin Minsky of MIT, colleagues at BBN, Fredkin, and others on “time-sharing” of the machine. By 1962 the technique was established, and BBN commenced time-sharing service connecting an external memory unit.

During his BBN days Licklider set up a plan for research on future library systems as a prototype of an envisioned network of thinking centers. Though interrupted by his service at the Advanced Research Projects Agency from 1962 to 1964, this research came to fruition in his book Libraries of the Future, published in 1965. In it, Licklider set forth a technological vision for a “procognitive system,” which was a layered computer network system allowing users to access stored information from consoles.

Human Factors in Man-Machine Systems . The SAGE system was designed to automate a preexistent information system, because manual procedures for transmitting military information through telephone and teletype systems lacked speed and precision. But in fact SAGE had to include human elements, such as computer operators who helped with the procedures and commanders who conducted the decision-making process. As a psychologist whose major area of research was function of the brain and human intelligibility, Licklider was skeptical about early realization of a complete automation of the system that included human decision-making and problem-solving. So he coined the term “man-computer symbiosis” to denote semiautomatic systems that include human factors. In 1958 he wrote the report “Man-Computer Symbiosis: Part of the Oral Report of the 1958 NAS-ARDC Special Study, Presented on Behalf of the Committee on the Roles of Men in Future Air Force Systems, 20–21 November 1958.” Licklider argued that it would be many years before “developments in artificial intelligence make it possible for machines alone to do much thinking or problem solving of military significance” (p. 4). Because the system had to include human elements, he stressed the importance of the research area called “man-computer communication,” which included the design of programming languages and other related areas that later would be called “human-computer interaction” (HCI).

In the academic sphere of psychology, such human-factors research emerged as engineering psychology. Actually, around 1960 this interdisciplinary area was called by various names, such as “human engineering,” “biomechanics,” “applied experimental psychology,” and “ergonomics.” In 1957 the American Psychological Association announced the formation of the new division of the Society of Engineering Psychologists in an effort to form an academic area that would gather research results on the human element in man-machine systems. Licklider was so supportive of the establishment of this academic field that he served on the editorial board of a newly published periodical, Human Factors, in late 1950s, published “Man-Computer Symbiosis” in 1960 as the first paper in the first issue of IRE Transactions on Human Factors in Electronics, and in 1961–1962 served as the fifth president of the Society of Engineering Psychologists. In addition, he received the society’s Franklin V. Taylor Award in 1965.

While the 1958 “Man-Computer Symbiosis” report had been situated within the military context, the 1960 version was generalized and academically shaped as a manifesto of the research area of human-machine communication in computing, though some of the elements already laid out in the 1958 report were reused. In the introduction of the 1960 paper Licklider tried to differentiate man-computer symbiosis from artificial intelligence and suggested that a computer could be an ideal partner for human beings in “formulative thinking,” which would be preferable to complete automation of the man-machine system. The paper insisted that online real-time computing would be needed for a symbiotic thinking system, as about 85 percent of “‘thinking’ time was devoted mainly to activities that were essentially clerical or mechanical: searching, calculating, plotting, transforming, determining the logical or dynamic consequences of a set of assumptions or hypotheses, preparing the way for a decision or an insight” (p. 6), and computers could help such “routinizable, clerical operations that fill the intervals between decisions” (p. 7). Then Licklider itemized five prerequisites for realization of man-computer symbiosis, such as memory hardware and organization, programming languages, and input-output devices. Among these prerequisites, the first item he pointed out was “speed mismatch between men and computers,” for which he insisted that time-sharing systems were needed. He continued:

It seems reasonable to envision, for a time 10 or 15 years hence, a “thinking center” that will incorporate the functions of present-day libraries together with anticipated advances in information storage and retrieval and the symbiotic functions suggested earlier in this paper. The picture readily enlarges itself into a network of such centers, connected to one another by wide-band communication lines and to individual users by leased wire services. In such a system, the speed of the computers would be balanced, and the cost of the gigantic memories and the sophisticated programs would be divided by the number of users. (p. 7)

In this paper, Licklider’s idea of a network of thinking centers is not stressed as a priority, which is typical of the way he presented things: In writings where he accentuated the importance of development of online real-time computing, the idea of a network of thinking centers was mentioned as an application. But when he put the priority of description on the network of thinking centers, as in “Truly SAGE system” or Libraries of the Future, Licklider explained the network scheme first.

Information Processing Techniques Office . Under the Kennedy administration, command and control systems were to be improved, so the Office of the Director of Defense Research and Engineering assigned a command and control project to the Advanced Research Projects Agency (ARPA) in June 1961. When the Department of Defense set up the Office for Behavioral Sciences and Command & Control Research in the ARPA in 1962, Licklider became its first director and stayed there until 1964. He renamed the office as the Information Processing Techniques Office (IPTO); its budget surpassed the sum of all other federal funding agencies’ budgets for the computing field of the time.

Licklider adopted a strategy of dividing the budget among only a handful of organizations, and eight groups of institutions to be funded were related to “time-sharing” in 1963. However, the early time-sharing systems could not sustain the man-computer interaction through graphics, which was indispensable for the IPTO’s primary objective, the advancement of command and control systems toward the ultimate goal of its automation. One rationale for support of the development of time-sharing systems was laid out in his paper “Artificial Intelligence, Military Intelligence, and Command and Control” in Military Information Systems (1964), based on the First Congress on the Information System Sciences held in November 1962. There Licklider argued that a complex information system required large programming tasks and that a large, fast computer based upon the concept of “sensibly simultaneous time sharing” could be economically used to facilitate the efforts of one programmer. In August 1963 Licklider clearly articulated his interest in time-sharing in his talk “Problems in Man-Computer Communications” at the fourth NATO Symposium on Communication Processes, saying that “the truly important thing is not interaction between one man and a computer, but interaction between several or many men and a computer” (Proceedings, p. 260).

At the same time, Licklider also showed his enthusiasm for constructing a network in an internal document sometimes referred to as the “Intergalactic Computer Network” memo. The subject of the memo was “Topics for Discussion at the Forthcoming Meeting,” dated 25 April 1963 and sent to the principal investigators he funded, whom he called “Members and Affiliates of the Intergalactic Computer Network.” He wrote: “It will possibly turn out, I realize, that only on rare occasions do most or all of the computers in the overall system operate together in an integrated network. It seems to me to be interesting and important, nevertheless, to develop a capability for integrated network operation” (p. 4). He then continued for three of the memo’s eight pages with a detailed description of hypothetical computer network usage at a console that includes cathode-ray-tube display, light-pen, and typewriter by an experimental psychologist. Toward the end of the memo, he noted: “The fact is, as I see it, that the military greatly needs solutions to many of most of the problems that will arise if we tried to make good use of the facilities that are coming into existence” (p. 7). Thus, although there was no explanation of the direct military need for time-sharing systems or their networking, Licklider tried to convince researchers that the development of time-sharing systems would benefit the military as a consequence. During his administration, however, networking was not seriously pursued. Instead, the IPTO’s strong interest in time-sharing made it one of the main research agendas in computer field.

Other than time-sharing, artificial intelligence received the most funding from the IPTO from 1962 to 1975. Licklider did not expect that it would suffice for full automation of command and control systems, but rather that its techniques would further flexible, interactive computing. Whereas he refrained from allocating a large budget to BBN in order to avoid conflict of interest, he did help the formation of a center of excellence at MIT headed by Robert Fano and called Project MAC, which simultaneously stood for Machine-Aided Cognition as a goal and Multiple-Access Computer as a tool. To advance human-computer interaction research, Licklider recommended Ivan E. Sutherland, whose seminal dissertation “Sketchpad: A Man-Computer Graphical Communication System” was submitted to MIT in 1963, as his successor at the IPTO. There Sutherland set up an academic research agenda and funding scheme for computer graphics as one of the most advanced areas of human-computer communication research. During the 1960s the computer field was institutionalized as “computer science” in academia, and the IPTO funding had an influence on it, both through the selection of funding areas and through support for leading figures in universities such as MIT, Carnegie Mellon, University of California at Berkeley and Los Angeles, University of Utah, and Stanford.

Computer Science at MIT . After his term at the IPTO, Licklider served as a consultant to the director of research of the International Business Machines Corporation (IBM) from 1964 to 1966. Even during this period, Licklider also was an impetus to the establishment of Project Intrex at MIT, beginning with his participation in its Planning Conference on Information Transfer Experiments held from 2 August to 3 September 1965. This project focused on an information network for university libraries and the online usage and community it would bear. Licklider wrote four of the twenty-three papers selected for presentation, including “An On-Line Information Network,” “Proposed Experiments in Browsing,” “The Nature of the Experiments to be Carried Out by Project Intrex,” and “A Technique of Measurement That May Be Useful in Project Intrex Experiments.” On 1 December 1966 he returned to MIT as professor of electrical engineering and headed Project MAC from 1968 to 1970. In 1969 Licklider was nominated for membership in the National Academy of Science in the psychology section, though he then switched to the engineering section instead.

In 1968, with the IPTO’s third director, Robert W. Taylor, who had initiated the ARPA Networking Project to connect the time-sharing systems it funded, Licklider coauthored a paper, “Computer as a Communication Device.” In this joint paper they envisioned a networked society, several months before the launch of the ARPA’s network in 1969.

Because Project MAC had two different objectives, in 1970 Marvin Minsky seceded from it to establish the MIT Artificial Intelligence Laboratory, and Project MAC was renamed in 1975 as the MIT Laboratory for Computer Science (LCS). After a short return to the IPTO from 1974 to 1975, without significant new initiatives on this second duty, Licklider came back to LCS and stayed there through his mandatory retirement in 1985 until his death in 1990.

J. C. R. Licklider was a member of the National Academy of Sciences, the American Academy of Arts and Sciences, the New York Academy of Sciences, and the Washington Academy of Sciences.

BIBLIOGRAPHY

The personal papers of J. C. R. Licklider are kept in Manuscript Collections, MC 499, Institute Archives and Special Collection, MIT Libraries, Massachusetts Institute of Technology. Some curricula vitae and bibliographies prepared by Licklider himself exist in the manuscripts.

WORKS BY LICKLIDER

Books and Chapter Articles

“Basic Correlates of the Auditory Stimulus.” In Handbook of Experimental Psychology, edited by S. S. Stevens. New York: Wiley, 1951.

“The Manner in Which and Extent to Which Speech Can Be Distorted and Remain Intelligible.” In Cybernetics: Circular Causal and Feedback Mechanisms in Biological and Social Systems. Transactions of the Seventh Conference March 23–24, 1950, New York, N. Y., edited by Heinz von Foerster. New York: Josiah Macy Jr. Foundation, 1951.

With George A. Miller. “The Perception of Speech.” In Handbook of Experimental Psychology, edited by S. S. Stevens. New York: Wiley, 1951.

“Artificial Intelligence, Military Intelligence, and Command and Control.” In Military Information Systems: The Design of Computer-Aided Systems for Command, edited by Edward E. Bennett, James Degan, and Joseph Spiegel. New York: Frederick A. Praeger, 1964.

Libraries of the Future. Cambridge, MA: MIT Press, 1965.

“An On-Line Intellectual Community” (Appendix B), “Proposed Experiments in Browsing” (Appendix I), “In Nature of the ‘Experiments’ to Be Carried Out by Project Intrex” (Appendix L), and “A Technique of Measurement That May Be Useful in Project Intrex Experiments” (Appendix O). In Intrex: Report of a Planning Conference on Information Transfer Experiments, edited by Carl F. J. Overhage and R. Joyce Harman. Cambridge, MA: MIT Press, 1965.

“Problems in Man-Computer Communications.” In Communication Processes, Proceedings of a Symposium Held in Washington, 1963, edited by Frank A. Geldard. New York: Macmillan, 1965.

“Man-Computer Communication.” In Annual Review of Information Science & Technology, edited by Carlos A. Cuadra. Chicago: Encyclopaedia Britannica, 1968.

“Communication and Computers.” In Communication, Language, and Meaning, edited by George A. Miller. New York: Basic Books, 1973.

“Potential of Networking for Science and Education.” In Networks for Research and Education: Sharing Computer and Information Resources Nationwide, edited by Martin Greenberger et al. Cambridge, MA: MIT Press, 1974.

“Computers and Government.” In The Computer Age: A Twenty-Year View, edited by Michael L. Dertouzos and Joel Moses. Cambridge, MA: MIT Press, 1979.

Journal or Other Periodical Articles

With J. C. Webster. “The Discriminabilitv of Interaural Phase Relations in Two-Component Tones.” Journal of the Acoustical Society of America 22 (1950): 191–195.

“The Intelligibility of Amplitude-Dichotomized Time-Quantized Speech Waves.” Journal of the Acoustical Society of America 22 (1950): 820–823.

With George A. Miller. “The Intelligibility of Interrupted Speech.” Journal of the Acoustical Society of America 22 (1950): 167–173.

With J. C. Webster and J. M. Hedlun. “On the Frequency Limits of Binaural Beats.” Journal of the Acoustical Society of America 22 (1950): 468–473.

“A Duplex Theory of Pitch Perception.” Experientia 7 (1951): 127–134.

“On the Process of Speech Perception.” Journal of the Acoustical Society of America 24 (1952): 590–594.

“Man-Computer Symbiosis.” IRE Transactions on Human Factors in Electronics 1 (1960): 4–10. Reprinted in Perspective on the Computer Revolution, edited by Zenon W. Pylyshyn, 306–318. Englewood Cliffs, N.J.: Prentice Hall, 1970.

With Welden E. Clark. “On-Line Man-Computer Communication.” Proceedings of Spring Joint Computer Conference 21 (1962): 113–128.

“Periodicity Pitch and Related Auditory Process Models.” International Audiology 1 (1962): 11–36.

With John McCarthy, Sheldon Boilen, and Edward Fredkin. “A Time-Sharing Debugging System for a Small Computer.” Proceedings of Spring Joint Computer Conference 23 (1963): 51–57.

“Man-Computer Partnership.” International Science & Technology (May 1965): 18–26.

With Daniel G. Bobrow, R. Y. Kain, and Bertram Raphael. “A Computer-Program System to Facilitate the Study of Technical Documents.” American Documentation 17 (1966): 186–189.

With Robert W. Taylor and Evan Herbert. “Computer as a Communication Device.” Science & Technology 76 (1968): 21–31.

With A. Vezza. “Applications of Information Technology.” Proceedings of the IEEE 66 (1978): 1330–1346.

OTHER SOURCES

Aspray, William, and Arthur L. Norberg. “J. C. R. Licklider.” OH 150. 28 October 1988, Cambridge, MA; Charles Babbage Institute, University of Minnesota, Minneapolis. A scholarly oral history record.

“Bolt Beranek and Newman: The First 40 Years.” Special issues, IEEE Annals of the History of Computing 27, no. 2 (2005); 28, no. 1 (2006). Some of these papers refer to Licklider’s contribution in the establishment of BBN’s role in the history of computing and networking: Leo Beranek, “BBN’s Earliest Days: Founding a Culture of Engineering Creativity” (27, no. 2: 6–14); John A. Swets, “ABC’s of BBN: From Acoustics to Behavioral Sciences to Computers” (27, no. 2: 15–29); Sheldon Baron, “Control Systems R&D at BBN” (27, no. 2: 52–64); Wallace Feurzig, “Educational Technology at BBN” (28, no. 1: 18–31); John Makhoul “Speech Processing at BBN” (28, no. 1: 32–45); Ralph Weischedel, “Natural-Language Understanding at BBN” (28, no. 1: 46–55).

Fano, Robert M. “Joseph Carl Robnett Licklider: March 11, 1915–June 26, 1990.” Biographic Memoirs 75 (1998): 190–213.

Garfinkel, Simon L. Architects of the Information Society: 35 Years of the Laboratory for Computer Science at MIT. Edited by Hal Abelson. Cambridge: MIT Press, 1999. As a book on the history of Project MAC and LCS, it refers to Licklider and contains a few images of him. It is based on an MIT-centered history account and stresses the importance of Licklider’s idea of the “Intergalactic Computer Network” as the origin of the network development at the ARPA.

Kita, Chigusa Ishikawa. “J. C. R. Licklider’s Vision for the IPTO.” IEEE Annals of the History of Computing 25, no. 3 (2003): 62–77. An extended version of this work is published as a book in Japanese, J. C. R. Licklider and His Age. Tokyo: Seido-sha, 2003.

Lee, John A. N., and Robert Rosin. “The Project MAC Interviews.” IEEE Annals of the History of Computing 14, no. 2 (1992): 14–35. This is a record of group interview (10 October 1988) that includes a biographical sketch of Licklider related to the early history of interactive computing at MIT. Participants are Fernando J. Corbató, Robert M. Fano, Martin Greenberger, Joseph C. R. Licklider, Douglas T. Ross, and Allan L. Scherr, as listed. (This entire Annals issue is dedicated to Project MAC.)

Norberg, Arthur L. “Changing Computing: The Computing Community and DARPA.” IEEE Annals of the History of Computing 18, no. 2 (1996): 40–53.

Norberg, Arthur L., and Judy E. O’Neill, with contributions by Kerry J. Freedman. Transforming Computer Technology: Information Processing for the Pentagon, 1962–1986. Baltimore: Johns Hopkins University Press, 1996. Most reliable history book on IPTO based on the historical documents of the agency that include normally inaccessible records.

O’Neill, Judy E. “The Role of ARPA in the Development of the ARPANET, 1961–1972.” IEEE Annals of the History of Computing 17, no. 4 (1995): 76–81.

Waldrop, M. Mitchell. The Dream Machine: J. C. R. Licklider and the Revolution That Made Computing Personal. New York: Viking, 2001. Biographical history book for general readers based on documents and interviews. Author’s interviews with Louise Licklider and others result in a lively description of Licklider’s personality.

Chigusa Ishikawa Kita