Quotes from Carl Sagan

There were excesses in science and there were excesses in religion. A reasonable man wouldn't be stampeded by either one. There were many interpretations of Scripture and many interpretations of the natural world. Both were created by God, so both must be mutually consistent. Wherever a discrepancy seems to exist, either a scientist or a theologian—maybe both—hasn't been doing his job. Palmer

Cosmos is closed and light cannot escape from it, then it may be perfectly correct to describe the universe as a black hole. If you wish to know what it is like inside a black hole, look around you.

Most of us are for freedom of expression when there's a danger that our own views will be suppressed. We're not all that upset, though, when views we despise encounter a little censorship here and there.

The ancient Ionians were the first we know of to argue systematically that laws and forces of Nature, rather than gods, are responsible for the order and even the existence of the world.

Demon" means "knowledge" in Greek. "Science" means "knowledge" in Latin. A jurisdictional dispute is exposed, even if we look no further.

The universe belongs to those who, at least to some degree, have figured it out.

A universe that is unknowable is no fit place for a thinking being. The ideal universe for us is one very much like the universe we inhabit.

Let's see if I got this right, she would say to herself. I've taken an inert gas that's in the air, made it into a liquid, put some impurities in a ruby, attached a magnet, and detected the fires of creation.

Adolf Hitler! Ken, it makes me furious. Forty million people die to defeat that megalomaniac, and he's the star of the first broadcast to another civilization? He's representing us. And them. It's that madman's dream come true.

Ever been in love?' The question was direct, matter-of-fact. 'Halfway, half a dozen times. But'—she glanced at the nearest telescope—there was always so much noise, the signal was hard to find.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light.

There are already cardiac pacemakers that can sense the beat of the human heart; only when there is the slightest hint of fibrillation does the pacemaker stimulate the heart. This is a mild but very useful sort of machine intelligence. I cannot imagine the wearer of this device resenting its intelligence. I

The idea of science as a method rather than as a body of knowledge is not widely appreciated outside of science, or indeed in some corridors inside of science.

The only planet we are sure is inhabited is a tiny speck of rock and metal, shining feebly by reflected sunlight, and at this distance utterly lost.

While the style of the critique may vary with the character of the critic, overly polite criticism benefits neither the proponents of new ideas nor the scientific enterprise.

It is very difficult to evolve by altering the deep fabric of life; any change there is likely to be lethal. But fundamental change can be accomplished by the addition of new systems on top of old ones…Thus evolution by addition and the functional preservation of the preexisting structure must occur for one of two reasons-either the old function is required as well as the new one, or there is no way of bypassing the old system that is consistent with survival.

This will rise to ten million annual deaths by 2020—in part because of a massive advertising campaign to portray smoking as advanced and fashionable to young women in the developing world.

New generations grew to maturity wholly ignorant of the sky that had transfixed their ancestors and that had stimulated the modern age of science and technology.

Things had been falling down since the beginning of time.

Tyrants and autocrats have always understood that literacy, learning, books and newspapers are potentially dangerous. They can put independent and even rebellious ideas in the heads of their subjects.

She was determined to be as tough-minded as possible, without abandoning the sense of wonder that was driving her in the first place.

Kepler's second law: A planet sweeps out equal areas in equal times. It takes as long to travel from B to A as from F to E as from D to C; and the shaded areas BSA, FSE and DSC are all equal.

Kepler's third or harmonic law states that the squares of the periods of the planets (the times for them to complete one orbit) are proportional to the cubes of their average distance from the Sun; the more distant the planet, the more slowly it moves, but according to a precise mathematical law: P2 = a3, where P represents the period of revolution of the planet about the Sun, measured in years, and a the distance of the planet from the Sun measured in "astronomical units.

Columbus therefore cheated on his calculations, as the examining faculty of the University of Salamanca quite correctly pointed out. He used the smallest possible circumference of the Earth and the greatest eastward extension of Asia he could find in all the books available to him, and then exaggerated even those. Had the Americas not been in the way, Columbus' expeditions would have failed utterly.