Quotes from Carl Sagan

But if humans can make new varieties of plants and animals, must not nature do so also? This related process is called natural selection. That life has changed fundamentally over the aeons is entirely clear from the alterations we have made in the beasts and vegetables during the short tenure of humans on Earth, and from the fossil evidence.

We have examined the universe in space and seen that we live on a mote of dust circling a humdrum star in the remotest corner of an obscure galaxy. And

I do not know what I may appear to the world; but to myself I seem to have been only like a boy, playing on the seashore, and diverting myself, in now and then finding a smoother pebble or a prettier shell than ordinary, while the great ocean of truth lay all undiscovered before me.

The first two letters of the name Pluto are the initials of Percival Lowell. Its symbol is , a planetary monogram. But Lowell's lifelong love was the planet Mars. He was electrified by the announcement in 1877 by an Italian astronomer, Giovanni Schiaparelli, of canali on Mars.

If the one-year-old, the five-year-old, the twelve-year-old, and the twenty-year-old all find compatible personalities in the beloved, there is a real chance to keep all of these sub-personas happy.

Biology is more like history than it is like physics. You have to know the past to understand the present. And you have to know it in exquisite detail.

There is a place with four suns in the sky-red, white, blue, and yellow; two of them are so close together that they touch, and star-stuff flows between them. I know of a world with a million moons. I know of a sun the size of the Earth-and made of diamond....The universe is vast and awesome, and for the first time we are becoming part of it

An oak tree and I are made of the same stuff. If you go far enough back, we have a common ancestor. The

Practitioners of pop science were once called Paradoxers, a quaint nineteenth-century word used to describe those who invent elaborate and undemonstrated explanations for what science has understood rather well in simpler terms. We

One of the reasons for its success is that science has built-in, error-correcting machinery at its very heart. Some may consider this an overbroad characterization, but to me every time we exercise self-criticism, every time we test our ideas against the outside world, we are doing science. When we are self-indulgent and uncritical, when we confuse hopes and facts, we slide into pseudoscience and superstition. Every

Superstition [is] cowardice in the face of the Divine

Predictions of surprising events always prove more accurate if not set down on paper beforehand.

what is wanted is not the will to believe, but the desire to find out, which is the exact opposite.

Other things being equal, it is better to be smart than to be stupid. Intelligent beings can solve problems better, live longer, and leave more offspring. Until the invention of nuclear weapons, intelligence powerfully aided survival.

Each plant and animal is exquisitely made; should not a supremely competent Designer have been able to make the intended variety from the start? 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).

When we are asked to swear in American courts of law—that we will tell "the truth, the whole truth, and nothing but the truth"—we are being asked the impossible. It is simply beyond our powers. Our memories are fallible; even scientific truth is merely an approximation; and we are ignorant about nearly all of the Universe. Nevertheless, a life may depend on our testimony.

Whatever their neurological and molecular antecedents, hallucinations feel real. They are sought out in many cultures and considered a sign of spiritual enlightenment.

As in all such technological nightmares, the principal task is to foresee what is possible; to educate use and misuse; and to prevent its organizational, bureaucratic and governmental abuse.

it does not become us to be so curious and inquisitive in these Things which the Supreme Creator seems to have kept for his own Knowledge: For since he has not been pleased to make any farther Discovery or Revelation of them, it seems little better than presumption to make any inquiry into that which he has thought fit to hide. But these Gentlemen must be told

The progress and perfection of mathematics are linked closely with the prosperity of the state.

Lost somewhere between the eternity of time and immensity of space is our tiny planetary home

But you reassure yourself that at least here they are safe from baleen whales and oil slicks and cocktail sauce.

There are no forbidden questions in science, no matters to sensitive or delicate to be probed, no sacred truths. That openness to new ideas, combined with the most rigorous, skeptical scrutiny of all ideas, sifts the wheat from the chaff. It makes no difference how smart, august, or beloved you are. You must prove your case in the face of determined, expert criticism. Diversity and debate are valued. Opinions are encouraged to contend–substantively and in depth.

The level of public education in science and technology is an important sign of the national scientific accomplishment. It is a matter of overall importance in economic development, scientific advance, and the progress of society.