Heinz von Foerster (born Heinz von Förster; November 13, 1911, Vienna – October 2, 2002, Pescadero, California) was an Austrian American scientist combining physics and philosophy. Together with Warren McCulloch, Norbert Wiener, John von Neumann, Lawrence J. Fogel, and others, Heinz von Foerster was an architect of cybernetics.
Von Foerster was born in 1911 in Vienna, Austria-Hungary, as Heinz von Förster. He was the grandson of Austrian architect Emil Ritter von Foerster. He studied physics at the Technical University of Vienna and at the University of Breslau, where in 1944 he received a Ph.D. in physics.
He moved to the USA in 1949, and worked at the University of Illinois at Urbana-Champaign, where he was a professor of electrical engineering from 1951 to 1975. From 1962 to 1975 he also was professor of biophysics and 1958–75 director of the Biological Computer Laboratory. Additionally, in 1956–57 and 1963–64 he was a Guggenheim-Fellow. From 1963 to 1965 he was president of the Wenner-Gren-Foundation for anthropological research.
He knew well and was in conversation with John von Neumann, Norbert Wiener, Humberto Maturana, Francisco Varela, Gordon Pask, Gregory Bateson, Lawrence J. Fogel and Margaret Mead, among many others. He influenced generations of students as a teacher and inclusive, enthusiastic collaborator.
Von Foerster was influenced by the Vienna Circle and Ludwig Wittgenstein. He worked in the field of cybernetics and is known as the inventor of second-order cybernetics. He made important contributions to constructivism. He is also known for his interest in computer music and magic.
The electron tube laboratory 
In 1949 von Foerster started work at the University of Illinois Urbana-Champaign at the electron tube laboratory of the Electrical Engineering Department, where he succeeded Joseph Tykociński-Tykociner. With his students he developed many innovative devices, including ultra-high-frequency electronics
He also worked on mathematical models of population dynamics and developed a general model now called the "von Foerster Equation" 
Biological Computer Laboratory 
Macy conferences 
He was the youngest member of the core group of the Macy conferences and editor of the five volumes of Cybernetics (1949–1953), a series of conference transcripts that represent important foundational conversations in the field. It was von Foerster who suggested that Wiener's coinage "Cybernetics" be applied to this conference series, that had previously been called "Circular Causal and Feedback Mechanisms in Biological and Social Systems".
Doomsday Equation 
A 1960 issue of Science magazine included an article by von Foerster and his colleagues P.M.Mora and L.W.Amiot proposing a formula representing a best fit to available historical data on world population; the authors then predicted future population growth on the basis of this formula. The formula gave 2.7 billion as the 1960 world population and predicted that population growth would become infinite by Friday, November 13, 2026 - von Foerster's 115th birthday anniversary - a prediction that earned it the name "the Doomsday Equation."
Based on population data obtained from various sources, von Foerster and his students concluded that world population growth over the centuries was faster than an exponential. In such a situation, doubling-time decreases over time. Von Foerster's tongue-in-cheek prediction of Doomsday on November 13, 2026, was based on an extrapolation into the future of doubling-time, with the finding that doubling-time would decrease to zero on that date.
Responders to his Doomsday prediction objected on the grounds of the finite human gestation time of 9 months, and the transparent fact that biological systems rarely persist in exponential growth for any substantial length of time. Those who knew von Foerster could see in his rejoinders an evident sense of humor.
Doomsday Equation: recent research 
Recent research has confirmed the basic soundness of von Foerster's findings. The hyperbolic growth of the world population observed until the 1970s has recently been correlated to a non-linear second order positive feedback between demographic growth and technological development that can be spelled out as follows:
- technological growth implies an increase in carrying capacity, an increase in the number of people who can survive on any given plot of land
- demographic growth (more people) implies more potential inventors and hence an acceleration of technological growth
- accelerating technological growth causes accelerating growth of carrying capacity, in a positive feedback loop
- faster population growth likewise feeds back by accelerating growth of the number of potential inventors, and then even faster technological growth
- hence, even faster growth of the Earth's carrying capacity for people, and so on
See also 
- Logarithmic timeline
- Das Netz: interview with von Foerster, 2003
- Power law: The equation that he derived for the date calculated is one that nowadays is called a power law.
Von Foerster authored more than 100 publications. Books, a selection:
- 1949, Cybernetics: Transactions of the Sixth Conference, (editor), Josiah Macy Jr. Foundation: New York, 220 pp.
- 2002, Understanding understanding, a volume of von Foerster's papers, published by Springer-Verlag, 2002.
- 2010, with Monika Broecker: Part of the World. Fractals of Ethics - A Drama in Three Acts. Heinz von Foerster's most extensive biography. First published in German in 2002: with Monika Broecker. Teil der Welt. Fraktale einer Ethik - ein Drama in drei Akten.
Articles, a selection:
- 1958, "Basic Concepts of Homeostasis." In: Homeostatic Mechanisms, Upton, New York, pp. 216–242, 1958.
- 1960, "Doomsday: Friday, November 13, AD 2026," with P. M. Mora und L. W. Amiot, Science 132, pp. 1291–1295, 1960.
- 1961, "A Predictive Model for Self-Organizing Systems," Part I: Cybernetica 3, pp. 258–300; Part II: Cybernetica 4, pp. 20–55, with Gordon Pask, 1961.
- 1964, "Biological Computers," with W. Ross Ashby, In: Bioastronautics, K. E. Schaefer, Macmillan Co., New York, pp. 333– 360, 1964.
- 1969, "What is Memory that it may have Hindsight and Foresight"
- 1971, "Computing in the Semantic Domain"
- 1971, "Technology. What Will It Mean to Librarians?"
- The Heinz von Foerster Page
- See also de:Emil von Förster
- Segal, L. The Dream of Reality: Heinz Von Foerster's Constructivism, Springer, 2001. ISBN 0-387-95130-X
- See for example, in Review of Scientific Instruments 25: 640–653, 1954.
- "Some Remarks on Changing Populations" in The Kinetics of Cellular Proliferation, F. Stohlman, Jr., ed., Grune & Stratton, New York, pp. 382-407 (1959); E. Trucco, Bulletin of Mathematical Biophysics 27: 285-304 and 449-471, 1965
- Biological Computer Laboratory
- Heinz von Foerster, P. M. Mora and L. W. Amiot (November 1960). "Doomsday: Friday, 13 November, A.D. 2026. At this date human population will approach infinity if it grows as it has grown in the last two millenia". Science 132 (3436): 1291–1295. Bibcode:1960Sci...132.1291V. doi:10.1126/science.132.3436.1291. PMID 13782058.
- see, e.g., Introduction to Social Macrodynamics by Andrey Korotayev et al.
- The Bibliography of Heinz von Foerster 1943–2003, from Alexander Riegler, dec 2003 gives an overview of all his publications.
|Wikiquote has a collection of quotations related to: Heinz von Foerster|
- Asaro, Peter M. (2007). "Heinz von Foerster and the Bio-Computing Movements of the 1960s," in Albert Müller and Karl H. Müller (eds.) An Unfinished Revolution? Heinz von Foerster and the Biological Computer Laboratory | BCL 1958-1976. Vienna, Austria: Edition Echoraum.
- Stanford Humanities Review Interview
- The Heinz von Foerster Page
- Korotayev A., Malkov A., Khaltourina D. Introduction to Social Macrodynamics: Compact Macromodels of the World System Growth. Moscow: URSS, 2006. ISBN 5-484-00414-4 .
- Biological Computer Laboratory web site, University of Illinois
- An anthology of Circularity Principles from the Heinz von Foerster entry at The Cybernetics Society
- Gooch, Sherwin, & Nordin, Hud, "High Tech Heroes television interview, episode 10, part 1," Heinz von Foerster discusses the founding of Cybernetics, and the possibility of achieving immortality through prosthetic brains, Foothill College, California, August 22, 1989.
- "High Tech Heroes, episode 10, part 2."
- "Heinz Von Foerster Papers at the University of Illinois Archives"