Carl Sagan Quotes

We are the only species on the planet, so far as we know, to have invented a communal memory stored neither in our genes nor in our brains. The warehouse of this memory is called the library

We seem, these days, much more willing to recognize the perils before us than we were even a decade ago. The newly recognized dangers threaten all of us, equally. No one can say how it will turn out down here. But this is also, we may note, the first time that a species has become able to journey to the planets and the stars. Sailors on a becalmed sea, we sense a stirring of the breeze.

In science it often happens that scientists say, "You know that's a really good argument; my position is mistaken..."

If you look at Earth from space you see a dot, that's here. That's home. That's us. It underscores the responsibility to deal more kindly and compassionately with one another and to preserve and cherish that pale blue dot, the only home we've ever known.

Whenever our ethnic or national prejudices are aroused, in times of scarcity, during challenges to national self esteem or nerve, when we agonize about our diminished cosmic place and purpose, or when fanaticism is bubbling up around us - then, habits of thought familiar from ages past reach for the controls.

The fossil record implies trial and error, an inability to anticipate the future, features inconsistent with an efficient Great Designer (although not with a Designer of a more remote and indirect temperament)

Few scientists now dispute that today's soaring levels of carbon dioxide and other gases in the atmosphere will cause global temperature averages to rise by as much as nine degrees Fahrenheit sometime after the year 2000.

I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue.

As agonizing a disease as cancer is, I do not think it can be said that our civilization is threatened by it. ... But a very plausible case can be made that our civilization is fundamentally threatened by the lack of adequate fertility control. Exponential increases of population will dominate any arithmetic increases, even those brought about by heroic technological initiatives, in the availability of food and resources, as Malthus long ago realized.

The illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world.

We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose.

The library connects us with the insight and knowledge, painfully extracted from Nature, of the greatest minds that ever were, with the best teachers, drawn from the entire planet and from all our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species.

There is perhaps no better a demonstration of the folly of human conceits than this distant image of our tiny world.

We on Earth have just awakened to the great oceans of space and time from which we have emerged. We are the legacy of 15 billion years of cosmic evolution. We have a choice: We can enhance life and come to know the universe that made us, or we can squander our 15 billion-year heritage in meaningless self-destruction. What happens in the first second of the next cosmic year depends on what we do, here and now, with our intelligence and our knowledge of the cosmos.

We are made of star stuff. For the most part, atoms heavier than hydrogen were created in the interiors of stars and then expelled into space to be incorporated into later stars. The Sun is probably a third generation star.

It would be wryly interesting if in human history the cultivation of marijuana led generally to the invention of agriculture, and thereby to civilization.

There are many instances in science, where those closest to the intricacies of the subject have a more highly developed sense of its intractability than those at some remove. On the other hand, those at too great a distance may, I am well aware, mistake ignorance for perspective.

Absolute certainty will always elude us. We will always be mired in error. The most each generation can hope for is to reduce the error. . . .

Even Johannes Kepler, Isaac Newton, Charles Darwin, Gregor Mendel, and Albert Einstein made serious mistakes. But the scientific enterprise arranges things so that teamwork prevails: What one of us, even the most brilliant among us, misses, another of us, even someone much less celebrated and capable, may detect and rectify.

If all the suns but ours collapsed tonight, how many lifetimes would it take us to realize that we were alone?

The idea that God is an oversized white male with a flowing beard, who sits in the sky and tallies the fall of every sparrow is ludicrous. But if by 'God,' one means the set of physical laws that govern the universe, then clearly there is such a God. This God is emotionally unsatisfying... it does not make much sense to pray to the law of gravity.

My fundamental premise about the brain is that its workings - what we sometimes call "mind" - are a consequence of its anatomy and physiology, and nothing more.

I think the discomfort that some people feel in going to the monkey cages at the zoo is a warning sign.

We are all star stuff.

Humans - who enslave, castrate, experiment on, and fillet other animals - have had an understandable penchant for pretending animals do not feel pain.

We live on a mote of dust suspended in a sunbeam

What a splendid perspective contact with a profoundly different civilization might provide! In a cosmic setting vast and old beyond ordinary human understanding we are a little lonely, and we ponder the ultimate significance, if any, of our tiny but exquisite blue planet, the Earth.... In the deepest sense the search for extraterrestrial intelligence is a search for ourselves.

Science arouses a soaring sense of wonder. But so does pseudoscience. Sparse and poor popularizations of science abandon ecological niches that pseudoscience promptly fills. If it were widely understood that claims to knowledge require adequate evidence before they can be accepted, there would be no room for pseudoscience.

For a long time the human instinct to understand was thwarted by facile religious explanations.

I don't know the answer. Maybe no one knows. Maybe when you grow up, you'll be the first to find out.

For all our conceits about being the center of the universe, we live in a routine planet of a humdrum star stuck away in an obscure corner ... on an unexceptional galaxy which is one of about 100 billion galaxies. ... That is the fundamental fact of the universe we inhabit, and it is very good for us to understand that.

Extraordinary claim requires extraordinary proof.

It's hard to kill a creature once it lets you see its consciousness.

The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together. Information distilled over 4 billion years of biological evolution. Incidentally, all the organisms on the Earth are made essentially of that stuff. An eyedropper full of that liquid could be used to make a caterpillar or a petunia if only we knew how to put the components together.

We are, each of us, a multitude. Within us is a little universe.

The nuclear arms race is like two sworn enemies standing waist deep in gasoline, one with three matches, the other with five.

The brain is like a muscle. When it is in use we feel very good. Understanding is joyous.