Quotes from Carl Sagan

Science invites us to let the facts in, even when they don't conform to our preconceptions. It counsels us to carry alternative hypotheses in our heads and see which best fit the facts. It urges on us a delicate balance between no-holds-barred openness to new ideas, however heretical, and the most rigorous skeptical scrutiny of everything—new ideas and established wisdom. This kind of thinking is also an essential tool for a democracy in an age of change.

Natural selection has served as a kind of intellectual sieve, producing brains and intelligences increasingly competent to deal with the laws of nature.

It is not hard to imagine serious public dangers emerging out of instances in which political, military, scientific or religious leaders are unable to distinguish fact from vivid fiction.

Many pseudoscientific and New Age belief systems emerge out of dissatisfaction with conventional values and perspectives—and are therefore themselves a kind of skepticism.

But the creed of liberty means nothing if it is only our own liberty that excites us.

Except by sealing the brain off into separate airtight compartments, how is it possible to fly in airplanes, listen to the radio or take antibiotics while holding that the Earth is around 10,000 years old or that all Sagittarians are gregarious and affable?

People's feelings are as strong as they always were, and skepticism is probably as unfashionable today as in any other age. Accordingly

It is striking that the observational search for extraterrestrial life began in the same generation as the invention of the telescope, and with the greatest theoretician of the age.

esta mezcla combustible de ignorancia y poder nos explotará en la cara.

all the atoms that make each of us up—the iron in our blood, the calcium in our bones, the carbon in our brains—were manufactured in red giant stars thousands of light-years away in space and billions of years ago in time. We are, as I like to say, starstuff.

Plainly, there's something within me that's ready to believe in life after death. And it's not the least bit interested in whether there's any sober evidence for it. So I don't guffaw at the woman who visits her husband's grave and chats him up every now and then, maybe on the anniversary of his death. It's not hard to understand. And if I have difficulties with the ontological status of who she's talking to, that's all right. That's not what this is about. This is about humans being human.

We embarked on our journey to the stars with a question first framed in the childhood of our species and in each generation asked anew with undiminished wonder: What are the stars? Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.

The known is finite, the unknown infinite; intellectually we stand on an islet in the midst of an illimitable ocean of inexplicability. Our business in every generation is to reclaim a little more land. —T. H. Huxley

I Ã¢â'¬Â¦ had ambition not only to go farther than anyone had done before," wrote Captain James Cook, the eighteenth-century explorer of the Pacific, "but as far as it was possible for man to go." Two centuries later, Yuri Romanenko, on returning to Earth after what was then the longest space flight in history, said "The Cosmos is a magnet Ã¢â'¬Â¦ Once you've been there, all you can think of is how to get back.

Bishop John Wilkins commented in 1638 on these Athenians: "Those zealous idolators [counted] it a great blasphemy to make their God a stone, whereas notwithstanding they were so senseless in their adoration of idols as to make a stone their God.

There seem to be many people who simply wish to be told an answer, any answer, and thereby avoid the burden of keeping two mutually exclusive possibilities in their heads at the same 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.

the most important step we can take toward Mars is to make significant progress on Earth. Even modest improvements in the social, economic, and political problems that our global civilization now faces could release enormous resources, both material and human, for other goals.

When [faith] healers treat serious organic disease, they are responsible for untold anguish and unhappiness Ã¢â'¬Â¦ The healers become killers.

Pseudoscience is easier to contrive than science, because distracting confrontations with reality—where we cannot control the outcome of the comparison—are more readily avoided. The standards of argument, what passes for evidence, are much more relaxed. In part for these same reasons, it is much easier to present pseudoscience to the general public than science. But this isn't enough to explain its popularity.

Another contemporary example is the "war" on drugs—where the government and munificently funded civic groups systematically distort and even invent scientific evidence of adverse effects (especially of marijuana), and in which no public official is permitted even to raise the topic for open discussion.

Wisdom lies in understanding our limitations. 'For Man is a giddy thing,' teaches William Shakespeare.

The fifth regular solid must then, they thought, correspond to some fifth element that could only be the substance of the heavenly bodies.

If artificial selection can make such major changes in so short a period of time, what must natural selection, working over billions of years, be capable of? The answer is all the beauty and diversity of the biological world. Evolution is a fact, not a theory.