Teaching Notes

Aims. This simulation is designed to profile many features where science and public policy meet, at the same time that it portrays an historic moment in public postures towards the environment. The focus is Rachel Carson's Silent Spring and the concerns about chemical pesticides that it raised. Students situate themselves in 1963, shortly after the publication the book. The occasion for discussion is a Presidential Advisory Committee, similar to the one John F. Kennedy asked to advise him on this topic.

Format. There are 12-20 roles. Each student presents the perspective of one individual from the time (as testimony), then all adopt roles as members of the committee in crafting policy recommendations to the President. A (non-exhaustive) bibliography for each role and a list of common resources is provided. There is also a background essay on the introduction of DDT and on Rachel Carson and the history of her book. Additional information details news items, popular music and cartoons.

Science. The case of pesticides is an occasion for students to learn many scientific concepts: predator-prey and parasite-host interactions; population dynamics resulting from introduced species; food chains and bioaccumulation (or concentration of elements); natural selection and insecticide resistance; biodegradation (or persistence) of compounds; perhaps some aspects of toxicology and the physiology of poisons; agricultural productivity and monoculture; the multi-factorial complexity of individual ecosystems (even farm fields). In addition, Carson appealed to the "balance of nature," a concept now widely discredited. Use of pesticides, however, raises important questions about ecosystem stability and the (un)predictability of complex systems.

Science and Society. The case is also an occasion to discuss several important elements of science in society. First, the episode of Silent Spring prominently exemplifies the problem of expertise. Not everyone can be an expert. Who, then, can one trust? How does one establish an effective system of credibility? Who makes decisions: the experts or persons hopefully well informed by them? Second, what are the appropriate dimensions of public communication of science? In what ways are emotional portrayals appropriate or inappropriate? Are collective personal sentiments a justified basis of policy for the group?

Ethics. While science is central to decisions about the use of pesticides, many values are also relevant and worth profiling: reduction of suffering from disease; reduction of suffering from hunger; respect for wildlife; property rights and personal liberties; protection from health risks; long-term prudence (versus short-term expediency); and public versus private benefits. There is opportunity to discuss several aspects of environmental ethics. First, what is our obligation to non-human species? Do we protect wildlife only when it is convenient or serves our own aims, or are there intrinsic responsibilities? Second, what is the nature of our responsibilities to each other through the environment as a medium? Can these duties be articulated? Leaving events to economic forces (a laissez-faire approach) is itself a choice that involves values. Finally, what is the ethical status of "the control of nature," protrayed by Carson as inherently wrong?

History. This simulation was developed in part to help teach "historical perspectives" as part of a college's general education program. The aim is thus to capture the perspective, not replicate the history. Students are open to make whatever recommendations seem justified by the testimony and their reading. At the same time, it is important to discourage tendencies to anticipate the future and to make the history come out "right." Kennedy's own panel was his Science Advisory Committee; I have expanded the focus to allow broader discussion of Carson's claims -- say, about control of nature and attitudes towards the environment in general.

The following table lists the various issues and maps them to the particular roles:

	Carson Supporter	Carson Critic
credibility documentation of sources reliability of facts bias/balance of presentation rhetoric/tone/style	Cole (science) Brown Cottam Bookchin (content, style)	Diamond Stevens Larrimer? Baldwin (bias)
harm (non-target species) insect pollinators shared habitat food chain (*fish, birds) other	Cole Clement/Murphy Cottam	Stevens Baldwin?
benefits (target species!) crops: food/fiber/forest disease control nuisance/comfort		Rothberg Cole? Diamond Stevens Larrimer Zavon Baldwin (incl. forestry) Freeman?
safety food (carcinogens?) worker safety	Cole? Bookchin? [Baldwin]	Rothberg? Stevens? Zavon? Baldwin (workers)
insecticide resistance	Brown Cottam? Cole?	White-Stevens (alternatives)
indiscriminate use excess/runoff	Cole? Cottam: aerial emulsions Freeman?	Rothberg
alternatives: biological (+) earlier organics (-) pesticide persistence research	Cole?? *Freeman (biol.)	Baldwin: wary until further research
balance of nature	Clement	White-Stevens
control of nature	Clement	~Bookchin Cole White-Stevens

Guiding Discussion

The teacher may assume the role of Jerome Wiesner, Kennedy's Science Advisor, as a way to manage discussion as committee chair, or students may elect their own chair. Students tend to agree quickly on the easy solution of "more research." They might need further guidance or motivation to resolve the more challenging questions that take discussion deeper: