“His laws changed all of physics and astronomy. His laws made it possible to calculate the mass of the sun and planets. The way it's done is immensely beautiful. If you know the orbital period of any planet, say, Jupiter or the Earth and you know its distance to the Sun; you can calculate the mass of the Sun. Doesn't this sound like magic?We can carry this one step further - if you know the orbital period of one of Jupiter's bright moons, discovered by Galileo in 1609, and you know the distance between Jupiter and that moon, you can calculate the mass of Jupiter. Therefore, if you know the orbital period of the moon around the Earth (it's 27.32 days), and you know the mean distance between the Earth and the moon (it's about 200,039 miles), then you can calculate to a high degree of accuracy the mass of the Earth. … But Newton's laws reach far beyond our solar system. They dictate and explain the motion of stars, binary stars, star clusters, galaxies and even clusters of galaxies. And Newton's laws deserve credit for the 20th century discovery of what we call dark matter. His laws are beautiful. Breathtakingly simple and incredibly powerful at the same time. They explain so much and the range of phenomena they clarify is mind boggling. By bringing together the physics of motion, of interaction between objects and of planetary movements, Newton brought a new kind of order to astronomical measurements, showing how, what had been a jumble of confused observations made through the centuries were all interconnected.”

“The final mystery is oneself. When one has weighed the sun in the balance, and measured the steps of the moon, and mapped out the seven heavens star by star, there still remains oneself. Who can calculate the orbit of his own soul?”

“I myself have dreamed up a structure intermediate between Dyson spheres and planets. Build a ring 93 million miles in radius - one Earth orbit - around the sun. If we have the mass of Jupiter to work with, and if we make it a thousand miles wide, we get a thickness of about a thousand feet for the base.And it has advantages. The Ringworld will be much sturdier than a Dyson sphere. We can spin it on its axis for gravity. A rotation speed of 770 m/s will give us a gravity of one Earth normal. We wouldn't even need to roof it over. Place walls one thousand miles high at each edge, facing the sun. Very little air will leak over the edges.Lord knows the thing is roomy enough. With three million times the surface area of the Earth, it will be some time before anyone complains of the crowding.”

“Their mistake was the mistake of Galileo. He was right that the earth revolves around the sun, but he didn't know that the entire solar system revolves around yet another center; he didn't know that the real orbit of the earth, as opposed to the relative orbit, is by no means some naive circle...”

“Love was the secret behind everything...love was what made vineyards grow and filled the spaces between the stars, and fixed the ground beneath his feet. It didn't matter if you acknowledged it or not. You couldn't stop the motion of the earth or hold back the ocean tides, or break the pull of the moon. You couldn't stop the rain or pull a shade over the sun.”

“If you can see a thing whole, it seems that it's always beautiful. Planet,lives...But close up, a world's all dirt and rocks. And day to day, life's a hard job, you get tired, you lose the pattern. You need distance, interval. The way to see how beautiful the earth is, is to see it as the moon. The way to see how beautiful life is, is from the vantage point of death.”