Conservationists Jacques Cousteau and David Brower give us this helpful perspective: If the earth were the size of an egg, then all the water on the planet would be just a drop; all the air, if condensed to the density of water, would be a droplet only one-fortieth as big; and all the arable land would be a not-quite-visible speck of dust.

the fraction of the world’s cereals (currently one-third) being fed to livestock, an inefficient use of grain. Animals turn only about 10-45 percent of grain inputs into meat—5 percent or less in some cases.

For the average American, the daily flows of materials (other than water) total more than twenty times a person’s body weight, nearly all of it waste.

A fleet of 200 mpg, roomy, clean, safe, recyclable, renewably fueled cars might keep drivers from running out of oil, climate, or clean air, but they’d instead run out of roads, land, and patience—the new constraints du jour.

We spend $50 billion a year to guard sea lanes bringing oil from sources we would not need if the Reagan administration had not gutted light-vehicle efficiency standards in 1986.

They allocate scarce resources efficiently over the short term.

Why would the inhabitants of earth need a manual? Ideally, it would provide everyone with a shared mental model of the system they are influencing and participating in.

Less than 2 percent of the total waste stream is actually recycled—primarily paper, glass, plastic, aluminum, and steel.

These tools include institutional innovations that can create new markets in avoided resource depletion and abated pollution, maximize competition in saving resources, and convert the cost of a sulfur tax or a carbon-trading price into profits realized from the sale and use of efficient technologies.