Carl Sagan Quotes

Those who make uncritical observations or fraudulent claims lead us into error and deflect us from the major human goal of understanding how the world works. It is for this reason that playing fast and loose with the truth is a very serious matter.

As children, we fear the dark. Anything might be out. here. The unknown troubles us. Ironically, it is our fate to live in the dark. This unexpected finding of science is only about three centuries old. Head out from the Earth in any direction you choose, and — after an initial flash of blue and a longer wait while the Sun fades — you are surrounded by blackness, punctuated only here and there by the faint and distant stars. Even after we are grown, the darkness retains its power to frighten us. And so there are those who say we should not inquire too closely into who else might be living in that darkness. Better not to know, they say. There are 400 billion stars in the Milky Way Galaxy. Of this immense multitude, could it be that our humdrum Sun is the only one with an inhabited planet? Maybe. Maybe the origin of life or intelligence is exceedingly improbable. Or maybe civilizations arise all the time, but wipe themselves out as soon as they are able. Or, here and there, peppered across space, orbiting other suns, maybe there are worlds something like our own, on which other beings gaze up and wonder as we do about who else lives in the dark…Life is a comparative rarity. You can survey dozens of worlds and find that on only one of them does life arise and evolve and persist… If we humans ever go to these worlds, then, it will be because a nation or a consortium of them believes it to be to its advantage — or to the advantage of the human species… In our time we’ve crossed the Solar System and sent four ships to the stars… But we continue to search for inhabitants. We can’t help it. Life looks for life.

In the diagnosis of disease, Hippocrates introduced elements of the scientific method. He urged careful and meticulous observation: “Leave nothing to chance. Overlook nothing. Combine contradictory observations. Allow yourself enough time.

at least some paleontologists believe that the demise
of the dinosaurs was accelerated by nocturnal predation on reptilian eggs by the early mammals. Two chicken eggs for breakfast may be all-at least on the surface-that is left of this ancient mammalian cuisine.

We hear the crack of a bullwhip because its tip is moving faster than the speed of sound, creating a shock wave, a small sonic boom. A thunderclap has a similar origin. It was once thought that airplanes could not travel faster than sound. Today supersonic flight is commonplace. But the light barrier is different from the sound barrier. It is not merely an engineering problem like the one the supersonic airplane solves. It is a fundamental law of Nature, as basic as gravity. And there are no phenomena in our experience — like the crack of the bullwhip or the clap of thunder for sound — to suggest the possibility of traveling in a vacuum faster than light. On the contrary, there is an extremely wide range of experience — with nuclear accelerators and atomic clocks, for example — in precise quantitative agreement with special relativity.

And were the vision of Democritus to have been adopted by Western civilization, instead of being cast aside for the pale views of Plato and Aristotle, we would be vastly further ahead today, in

Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home.

We are made of star-stuff. Our bodies are made of star-stuff. There are pieces of star within us all.

It is the responsibility of scientists never to suppress knowledge, no matter how awkward that knowledge is, no matter how it may bother those in power; we are not smart enough to decide which pieces of knowledge are permissible, and which are not. …

Equally, where the technological application of scientific discoveries is clear and obvious — as when a scientist works on nerve gases — he cannot properly claim that such applications are “none of his business,” merely on the ground that it is the military forces, not scientists, who use the gases to disable or kill. This is even more obvious when the scientist deliberately offers help to governments, in exchange for funds.

Our feeblest contemplations of the Cosmos stir us — there is a tingling in the spine, a catch in the voice, a faint sensation, as if a distant memory, of falling from a height. We know we are approaching the greatest of mysteries.

Somos el producto de una larga serie de accidentes biológicos. En la perspectiva cósmica no hay razón alguna para pensar que seamos los primeros, los últimos o los mejores.

Writing is perhaps the greatest human inventions, binding together people, citizens of distant epochs, who never knew one another.

Each star system is an island in space, quarantined from its neighbors by the light-years. I can imagine creatures evolving into glimmerings of knowledge on innumerable worlds, every one of them assuming at first their puny planet and paltry few suns to be all that is. We grow up in isolation. Only slowly do we teach ourselves the Cosmos.

Cuando dirigimos nuestra vista al espacio vemos reflejadas en él las múltiples variedades de nuestra naturaleza.