Editing System dynamics (section)

==History==
System dynamics was created during the mid-1950s<ref>Forrester, Jay (1971). Counterintuitive behavior of social systems. Technology Review 73(3): 52–68</ref> by Professor [[Jay Forrester]] of the [[Massachusetts Institute of Technology]]. In 1956, Forrester accepted a professorship in the newly formed [[MIT Sloan School of Management]]. His initial goal was to determine how his background in science and engineering could be brought to bear, in some useful way, on the core issues that determine the success or failure of corporations. Forrester's insights into the common foundations that underlie engineering, which led to the creation of system dynamics, were triggered, to a large degree, by his involvement with managers at [[General Electric]] (GE) during the mid-1950s. At that time, the managers at GE were perplexed because employment at their appliance plants in Kentucky exhibited a significant three-year cycle. The [[business cycle]] was judged to be an insufficient explanation for the employment instability. From hand simulations (or calculations) of the stock-flow-feedback structure of the GE plants, which included the existing corporate decision-making structure for hiring and layoffs, Forrester was able to show how the instability in GE employment was due to the internal structure of the firm and not to an external force such as the business cycle. These hand simulations were the start of the field of system dynamics.<ref name="UDE">Michael J. Radzicki and Robert A. Taylor (2008). [http://www.systemdynamics.org/DL-IntroSysDyn/start.htm "Origin of System Dynamics: Jay W. Forrester and the History of System Dynamics"]. In: ''U.S. Department of Energy's Introduction to System Dynamics''. Retrieved 23 October 2008.</ref>

During the late 1950s and early 1960s, Forrester and a team of graduate students moved the emerging field of system dynamics from the hand-simulation stage to the formal [[computer modeling]] stage. Richard Bennett created the first system dynamics computer modeling language called SIMPLE (Simulation of Industrial Management Problems with Lots of Equations) in the spring of 1958. In 1959, [[Phyllis Fox]] and Alexander Pugh wrote the first version of
[[DYNAMO (programming language)|DYNAMO]] (DYNAmic MOdels), an improved version of SIMPLE, and the system dynamics language became the industry standard for over thirty years. Forrester published the first, and still classic, book in the field titled ''Industrial Dynamics'' in 1961.<ref name ="UDE"/>

From the late 1950s to the late 1960s, system dynamics was applied almost exclusively to corporate/managerial problems. In 1968, however, an unexpected occurrence caused the field to broaden beyond corporate modeling. [[John F. Collins]], the former mayor of Boston, was appointed a visiting professor of Urban Affairs at MIT. The result of the Collins-Forrester collaboration was a book titled ''Urban Dynamics''. The [[Urban Dynamics]] model presented in the book was the first major non-corporate application of system dynamics.<ref name ="UDE"/> In 1967, [[Richard M. Goodwin]] published the first edition of his paper "A Growth Cycle",<ref name="GROWTH">Goodwin, R.M. (1982). A Growth Cycle. In: Essays in Economic Dynamics. Palgrave Macmillan, London. [https://doi.org/10.1007/978-1-349-05504-3_12]</ref> which was the first attempt to apply the principles of system dynamics to economics. He devoted most of his life teaching what he called "Economic Dynamics", which could be considered a precursor of modern [[Non-equilibrium economics]].<ref name="GOODWIN">Di Matteo, M., & Sordi, S. (2015). Goodwin in Siena: economist, social philosopher and artist. Cambridge Journal of Economics, 39(6), 1507–1527. [http://www.jstor.org/stable/24695947]</ref> 

The second major noncorporate application of system dynamics came shortly after the first. In 1970, Jay Forrester was invited by the [[Club of Rome]] to a meeting in Bern, Switzerland. The Club of Rome is an organization devoted to solving what its members describe as the "predicament of mankind"—that is, the global crisis that may appear sometime in the future, due to the demands being placed on the Earth's [[carrying capacity]] (its sources of renewable and nonrenewable resources and its sinks for the disposal of pollutants) by the world's exponentially growing population. At the Bern meeting, Forrester was asked if system dynamics could be used to address the predicament of mankind. His answer, of course, was that it could. On the plane back from the Bern meeting, Forrester created the first draft of a system dynamics model of the world's socioeconomic system. He called this model WORLD1. Upon his return to the United States, Forrester refined WORLD1 in preparation for a visit to MIT by members of the Club of Rome. Forrester called the refined version of the model WORLD2. Forrester published WORLD2 in a book titled [[World Dynamics]].<ref name ="UDE"/>