The Chemical Industry
Because Carson refrains from naming particular corporations, the pesticide makers assume the monolithic shape of an evil empire in Silent Spring. Yet Carson does not preach at the industry. Yes, it develops hundreds of new deadly toxins a year, and, through disinformation and pressure on government agencies, it promotes their widest possible use—the book is very clear about these things. But Carson seems to view such activity as natural to the commercial enterprise and wastes no time calling on pesticide producers to reform themselves.

The Government
The government is the other great villain in Carson's story, and though one might think it is the chemical industry that bears primary responsibility for what has occurred, she is much more critical of public servants. Her thinking seems to be that more is to be expected of government. In succumbing to political pressure and helping pesticide makers promote their products, she argues, government has lost sight of its raison d'etre (reason for being), protecting the public interest. Carson holds that instead of echoing industry disinformation and spending taxpayers' money on reckless pest eradication programs, agencies like the Department of Agriculture and the Food and Drug Administration ought to impose stricter controls on the development, sale, and use of dangerous chemicals and to fund more research.

Nature
An overview of key figures in Silent Spring that did not mention nature would be quite incomplete. In terms of the amount of attention that is devoted to them, plant and animals are the most important "characters" in the book, surpassing humans by a wide margin, who are the focus of just a few chapters. Still, despite the almost infinite variety of life forms that Carson mentions, there emerges a single image of nature that has a crucial function in Carson's case against pesticides: nature as a fabric of life in which all things are connected, from the smallest of soil microbes to human beings and other large mammals. If readers accept such a view, they must also agree with Carson that the sledgehammer-like approach of current pest control—introducing large amounts of extremely toxic chemicals into the environment to eradicate a few species of insects—is indefensible. What poisons one part of the fabric of life poisons the whole.

The Public
Along with wildlife, the public is a major concern in Silent Spring. The image the book projects of this collective entity is that of a victim of the chemical industry, betrayed by irresponsible public officials and exposed to toxic pesticides at every turn. As the terrible side effects of pesticides become clearer, the public begins to ask questions, demand answers, and insist on greater responsiveness from government agencies.

The Visionaries
The heroes of Silent Spring come from several walks of life: scientists laboring patiently in an often tedious and seriously underfunded area of research to determine the precise scope of the pesticide threat; birders and other amateur naturalists, whose careful observation of wildlife in the field yields essential information about the problem; activists driven by a deep concern for their communities and the natural environment to challenge industry and government to behave more responsibly; and philosophers, writers, and other thinkers who help citizens understand the cultural sources not just of the pesticide problem but of the whole range of trouble that modern civilization has stirred up with technology. What all of these individuals share is an uncommon power discernment. Simply recognizing the broad impact of pesticides on the environment and health is a significant achievement. What makes Carson's visionaries even more remarkable is their having probed this tricky problem with great precision in the face of widespread disinformation and obstruction.