Carl Sagan Quotes

The astonishing fact is that similar mathematics applies so well to planets and to clocks. It needn’t have been this way. We didn’t impose it on the Universe. That’s the way the Universe is. If this is reductionism, so be it.

Nearly all our problems are made by humans and can be solved by humans. No social convention, no political system, no economic hypothesis, no religious dogma is more important.

The most significant aspect of the DNA story is that the fundamental processes of life now seem fully understandable in terms of physics and chemistry. No life force, no spirit, no soul seems to be involved. Likewise in neurophysiology: Tentatively, the mind seems to be the expression of the hundred trillion neural connections in the brain, plus a few simple chemicals.

But, Jefferson worried that the people - and the argument goes back to Thucydides and Aristotle - are easily misled. He also stressed, passionately and repeatedly, that it was essential for the people to understand the risks and benefits of government, to educate themselves, and to involve themselves in the political process.

Without that, he said, the wolves will take over.

Until fairly recently it was thought that humans had
fortv-eight chromosomes in an ordinary somatic cell. We now know that the correct number is forty-six. Chimps apparently really do have forty-eight chromosomes, and in this case a viable cross of a chimpanzee and a human would in any event be rare.

Science is not only compatible with spirituality; it is a profound source of spirituality. When we recognize our place in an immensity of light‐years and in the passage of ages, when we grasp the intricacy, beauty, and subtlety of life, then that soaring feeling, that sense of elation and humility combined, is surely spiritual. So are our emotions in the presence of great art or music or literature, or acts of exemplary selfless courage such as those of Mohandas Gandhi or Martin Luther King, Jr. The notion that science and spirituality are somehow mutually exclusive does a disservice to both.

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.

These are some of the things that hydrogen atoms do, given fifteen billion years of cosmic evolution.

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

El escepticismo tiene por función ser peligroso. Es un desafío a las instituciones establecidas. Si enseñamos a todo el mundo, incluyendo por ejemplo a los estudiantes de educación secundaria, unos hábitos de pensamiento escéptico, probablemente no limitarán su escepticismo a los ovnis, los anuncios de aspirinas y los profetas canalizados de 35.000 años. Quizá empezarán a hacer preguntas importantes sobre las instituciones económicas, sociales, políticas o religiosas. Quizá desafiarán las opiniones de los que están en el poder. ¿Dónde estaremos entonces?

The UFO abduction syndrom portrays, it seems to me, a banal Universe. The form of the supposed aliens is marked by a failure of the imagination and a preoccupation with human concerns. Not a single being presented in all these accounts is as astonishing as a cockatoo would be if you had never before beheld a bird.

In many myths, the one possibility the gods are most anxious about is that humans will discover some secret of immortality or even... attempt to stride the high heavens. ...It's a little bit like the rich imposing poverty on the poor and then asking to be loved because of it.

Arguments from authority carry little weight — “authorities” have made mistakes in the past. They will do so again in the future. Perhaps a better way to say it is that in science there are no authorities; at most, there are experts.

Every time a scientific paper presents a bit of data, it's accompanied by an error bar – a quiet but insistent reminder that no knowledge is complete or perfect. It's a calibration of how much we trust what we think we know. If the error bars are small, the accuracy of our empirical knowledge is high; if the error bars are large, then so is the uncertainty in our knowledge.

My parents were not scientists. They knew almost nothing about science. But in introducing me simultaneously to skepticism and to wonder, they taught me the two uneasily cohabiting modes of thought that are central to the scientific method. They were only one step out of poverty. But when I announced that I wanted to be an astronomer, I received unqualified support — even if they (as I) had only the most rudimentary idea of what an astronomer does. They never suggested that, all things considered, it might be better to be a doctor or a lawyer.