articulate the relevance of historical work to present-day debates without falling victim to what historians call “presentism” (misinterpreting historical events in the light of present-day knowledge or perspectives).

The third CHM Prize winner, A Vast Machine: Computer Models, Climate Data, and the Politics of Global Warming by Paul Edwards (MIT 2010, CHM Prize winner 2011) is an outstanding example of the potential for historians to contribute to broader public debates and give non-specialists insight into the work done by scientists and the process by which computer simulation has transformed scientific practice. Edwards tackles one of the most politically polarizing topics in U.S. science today: the connection of climate models to the real world. Without computers we could calculate average temperatures and plot trends, but only computer models can separate underlying climate trends from local or random fluctuations, project their future trend, or test explanations of the physical processes at work against the underlying data.

Our traditional idea of science, em-
braced by many scientists, is that sci-
entists collect objective observations
about the world and then formulate
theories to explain them. Scholars in
the field of science and technology
studies, in which Edwards is trained,
have instead stressed that nothing
can be perceived except through one
or another set of theories and assump-
tions. In climate science, as in much
modern science, data points from the
natural world become knowledge of a
kind that can support or challenge a
theory only after they are processed in
computer models. These models are
themselves based on theories. Thus,
as Edwards succinctly puts in an in-
troduction aimed at general readers,
“without models there are no data.”
This is not to say that Edwards is con-
tent, as some earlier radical scholars
in science and technology studies
were, simply to establish that the sci-
entific knowledge he is examining was
“socially constructed” and exit in tri-
umph. We have arrived at an odd mo-
ment where this strategy, once associ-
ated with the academic left, is now a
mainstay of the political right.

4. Computer technologies are always Political Eden Medina’s book Cybernetic Revolutionaries: Technology and Politics in Allende’s Chile (MIT 2011, CHM Prize winner 2012) takes a close look at the period from 1971 to 1973 when the British operations research specialist Stafford Beer was hired by Salvador Allende’s short-lived democratic Marxist government in Chile to implement his newly developed vision of cybernetic control. The boldest version of this Cybersym project imagined traditional political control replaced entirely by a new system in which decisions were influenced to the greatest possible extent by the input of ordinary citizens, industrial production was organized with the help of constantly updated computer models of the entire national economy, and decisions were based on information rather than bureaucratic self-interest. Beer modeled his plans on an abstracted view of the human nervous system in accordance with the central idea of cybernetics, which was that artificial, natural, and living systems are all governed by conceptually equivalent processes of feedback and control. Cybernetics originated in the 1940s with close ties to early work on computers and the support of many of the U.S.’s brightest minds across a range of disciplines. By the 1970s it was still fairly prominent in popular culture but was already sliding into obscure eccentricity within science as researchers favored more focused disciplinary approaches such as artifi-