"Economic logic requires that we maximize the productivity of the limiting factor in the short run, and invest in increasing its supply in the long run. When the limiting factor changes, then behavior that used to be economic becomes uneconomic. Economic logic remains the same, but the pattern of scarcity in the world changes, with the result that behavior must change if it is to remain economic. Instead of maximizing returns to and investing in man-made capital (as was appropriate in an empty world), we must now maximize returns to and invest in natural capital (as is appropriate in a full world). This is not “new economics,” but new behavior consistent with “old economics” in a world with a new pattern of scarcity."

"I'm no genius, and others can outwork me. What I do is ask the naive, honest questions, and then I’m not satisfied until I get the answers."

"The optimal scale of the economy is smaller, the greater (a) the degree of complementarity between natural and man-made capital; (b) our desire for direct experience of nature; and (c) our estimate of both the intrinsic and instrumental value of other species. The smaller the optimal scale of the economy, the sooner its physical growth becomes uneconomic."

"Even if we can never quantify [satisfaction or happiness]... as precisely as we currently quantify GNP,... perhaps it is better to be vaguely right than precisely wrong."

"The cosmology of scientific materialism … considers the cosmos an absurd accident, and life within it to be no more than another accident."

"The economy is a wholly owned subsidiary of the environment, not the reverse."

"Economists have focused too much on the economy’s circulatory system and have neglected to study its digestive tract. Throughput growth means pushing more of the same food through an ever larger digestive tract; development means eating better food and digesting it more thoroughly."

"Once we have replaced the basic premise of “more is better” with the much sounder axiom that “enough is best,” the social and technical problems of moving to a steady state become solvable, perhaps even trivial."

"If economic reality is actually so complex that it can only be described by complicated mathematical models that add epicycles to epicycles and externalities to externalities, then the reality should be simplified."

"Organisms cannot survive in a medium consisting of their own final outputs. Neither can economies."

"It is imaginable that someday we will discover how to create materials from nothing, how to achieve perpetual motion, how to reverse time’s arrow, and so on. But to take such science-fiction miracles as a basis for economic policy would be absurd."

"Current economic growth has uncoupled itself from the world and has become irrelevant. Worse, it has become a blind guide."

"There is something fundamentally wrong with treating the earth as if it were a business in liquidation."

"We have lived for 200 years in a growth economy. In this time we have come to believe that all our major economic ills – from unemployment and poverty to overpopulation and even environmental degradation – can be solved by more growth. And if the global economy existed in a void perhaps that would be true. But it does not."

"Instead the economy is a subsystem of the finite biosphere that supports it. When the economy’s expansion encroaches too much on the surrounding biosphere, we begin to sacrifice natural capital (animals, plants, minerals and fossil fuels) that is worth more than the manmade capital (roads, factories, appliances) added by ‘growth’."

"The notion of a steady state has meant different things at different times in history. To the traditional or classical economist, the steady state takes the biophysical dimensions of the planet — including population and available resources — as given and adapts technology and tastes to these objective conditions."