Let him look at that dazzling light hung aloft as an eternal lamp to lighten the universe; let him behold the earth, a mere dot compared with the vast circuit which that orb describes, and stand amazed to find that the vast circuit itself is but a very fine point compared with the orbit traced by the stars as they roll their course on high. But if our vision halts there, let imagination pass beyond; it will fail to form a conception long before Nature fails to supply material. The whole visible world is but an imperceptible speck in the ample bosom of Nature. No notion comes near it. Though we may extend our thought beyond imaginable space, yet compared with reality we bring to birth mere atoms. Nature is an infinite sphere whereof the centre is everywhere, the circumference nowhere. In short, imagination is brought to silence at the thought, and that is the most perceptible sign of the all-power of God.
Let man reawake and consider what he is compared with the reality of things; regard himself lost in this remote corner of Nature; and from the tiny cell where he lodges, to wit the Universe, weigh at their true worth earth, kingdoms, towns, himself. What is a man face to face with infinity?

One can truly say that the irresistible progress of natural science since the time of Galileo has made its first halt before the study of the higher parts of the brain, the organ of the most complicated relations of the animal to the external world. And it seems, and not without reason, that now is the really critical moment for natural science; for the brain, in its highest complexity—the human brain—which created and creates natural science, itself becomes the object of this science.

Our only complete assurance of surviving World War III is to halt it before it starts.

Overdrafts on aquifers are one reason some of our geologist colleagues are convinced that water shortages will bring the human population explosion to a halt. There are substitutes for oil; there is no substitute for fresh water.

The art of progress is to preserve order amid change and to preserve change amid order. Life refuses to be embalmed alive. The more prolonged the halt in some unrelieved system of order, the greater the crash of the dead society.

There is a poignant symbolism in the fact that the giant rockets now stand poised on the edge of the Pacific where the covered wagons halted only two lifetimes ago.

To halt the decline of an ecosystem, it is necessary to think like an ecosystem.

To use: Apply shampoo to wet hair. Massage to lather, then rinse. Repeat.
A typical hair-washing algorithm that fails to halt—in the way that computer programmers must avoid an infinite loop.

We are like the explorers of a great continent, who have penetrated its margins in most points of the compass and have mapped the major mountain chains and rivers. There are still innumerable details to fill in, but the endless horizons no longer exist.

We need to be realistic. There is very little we can do now to stop the ice from disappearing from the North Pole in the Summer. And we probably cannot prevent the melting of the permafrost and the resulting release of methane. In addition, I fear that we may be too late to help the oceans maintain their ability to absorb carbon dioxide. But there is something we can do—and it could make the whole difference and buy us time to develop the necessary low carbon economies. We can halt the destruction of the world’s rainforests—and even restore parts of them—in order to ensure that the forests do what they are so good at—in other words storing carbon naturally. This is a far easier, cheaper and quicker option than imagining we can rely on as yet unproven technology to capture carbon at a cost of some $50 per tonne or, for that matter, imagining we can achieve what is necessary through plantation timber.