Building democracy. For democracy to operate in practice as it is supposed to in theory, elections must be decided by a majority vote of all who are eligible and wish to vote, and limits must be imposed on the private funding of candidates for public office.

Population and women's rights. Women worldwide must be given the right to exercise freedom to make their own reproductive decisions, to have freedom over their own bodies. Contraception must be universally obtainable.

Sustainable energy. For the survival of civilization, the transition from fossil fuels to sun, wind, and greater efficiency of energy use must be expedited. There is no magic policy prescription; a combination of regulations, shifting subsidies, tax incentives, and education will be needed, as will an overall reduction in total energy consumption.

Health care for all. As the current pandemic teaches us, affordable health care must become a basic right for all citizens. Greater preparedness for the next pandemic, and surely there will be one, is also critical. We will learn a good deal over the coming months—and, whatever we learn, the lessons from Covid-19 should be implemented expeditiously.

Food security. Even with concerted action to reduce the intensity of global climate disruption, adequate water supply will remain a critical issue in food production. Reducing production of, and finding more efficient irrigation methods for highly water-demanding crops are critical. Organic farming appears to be the only viable long-term solution to food production if we want to avoid the risks of toxic pesticides and herbicides both in our food and in the runoff water that we drink downstream. Husbandry also needs reform to curtail the overuse of antibiotics in farm animals, which encourages potentially harmful mutations of pathogens, and to eliminate raising farm animals such as pigs and ducks under conditions that lead to the origination of diseases that can transfer to humans. Going vegetarian may be society's only option for sustainability.

Reducing inequality. Inequality of income and wealth is a kind of disease, and it, too, is pandemic. It weakens society and the power imbalances that create it are contagious. In addition to the ethical reasons for reducing inequality, doing so would probably result in a decrease in luxury consumption that harms the environment without providing life-sustaining benefits. Taxation is clearly the best cure for this disease.

Save biodiversity. All of the actions prescribed above would help stanch the increasing rate of loss of wild plants and animals. But they will not be enough. Protecting vast areas of natural habitat, where the human presence is minimal, is essential.

Fix universities. If I could, I would require that nobody graduates from my university with a degree in economics, business, law, engineering, or public policy without having taken a serious course in ecology and another one on thermodynamics and the entropy law. Ecologists should also learn economics. Indeed, let there be one major for all, "Complex Systems," with different emphases within, but a common core of knowledge.

Enhance rationality. Millions of Americans have doubts about whether global warming science is real and a substantial portion of our population has doubts about evolution. Denial of science can be a relatively harmless pastime provided it is done in the privacy of one's home. Indeed, the Constitution guarantees all of us the right to spout nonsense. But now anti-science threatens to alter the curricula of our public schools, as the creationists would do, and threatens to tear the legal fabric that protects our environment and our society. The citizens of a democracy must speak out in defense of rationality. When political leaders try to overturn the regulations that protect citizens and our natural heritage it is not merely overturning a legislative legacy of several decades. It is overturning a 500-year legacy of civilization that has steadily replaced faith in irrationality with acceptance of science. The long-term consequences of such actions will reverberate through the coming decades in ways that will degrade far more than the health of our environment and our material well-being; they will erode a very foundation of civilization.

In its climate action plan, Providence, Rhode Island, is giving frontline residents' health equal billing with carbon reduction. Other cities should pay attention.

A conversation on COVID-19 with the director of Harvard University's Center of Climate, Health and the Global Environment.