Carl Sagan Quotes

This country is about, in my judgment, aggressive, open debate. There is an old saying: When everyone is thinking the same thing, no one is thinking very much.

The power of real debate is in the language and intellectual honesty of the debaters, alongside the engagement of spectators.

He that cannot reason is a fool. He that will not is a bigot. He that dare not is a slave.

My music asks people to think critically, so how can I get upset when people think about me critically?

We cannot be so scared that our ideas or opinions will not survive being tested. If you are afraid of being wrong, then you might not have a good argument.

You don't have to think exactly like me. When people go, "I don't agree with everything you say," you know what, if you agree with everything anyone says, you're an idiot.

We must continually remind students in the classroom that expression of different opinions and dissenting ideas affirms the intellectual process. We should forcefully explain that our role is not to teach them to think as we do but rather to teach them, by example, the importance of taking a stance that is rooted in rigorous engagement with the full range of ideas about a topic.

Freethought is respectable. Freethought is crucial. Freethought needs to be publicized.

Don't be trapped by dogma — which is living with the results of other people's thinking.

I have always strenuously supported the right of every man to his own opinion, however different that opinion might be to mine. He who denies to another this right, makes a slave of himself to his present opinion, because he precludes himself the right of changing it.

Reason and free inquiry are the only effectual agents against error... They are the natural enemies of error, and of error only... If [free enquiry] be restrained now, the present corruptions will be protected, and new ones encouraged.

The idea that we should be open to all ideas is very different from the supposition that all ideas are equally valid.

I call that mind free which jealously guards its intellectual rights and powers, which calls no man master, which does not content itself with a passive or hereditary faith, which opens itself to light whencesoever it may come, which receives new truth as an angel from Heaven.

Freethinkers are generally those who never think at all.

Most Christians are afraid that people will think for themselves; most atheists are afraid that they won’t.

Thought must never submit, neither to a dogma, nor to a party, nor to a passion, nor to an interest, nor to a preconceived idea, nor to whatever it may be, save to the facts themselves, because, for thought, submission would mean ceasing to be.

Our weapons are the ironic mind against the literal: the open mind against the credulous; the courageous pursuit of truth against the fearful and abject forces who would set limits to investigation (and who stupidly claim that we already have all the truth we need). Perhaps above all, we affirm life over the cults of death and human sacrifice and are afraid, not of inevitable death, but rather of a human life that is cramped and distorted by the pathetic need to offer mindless adulation, or the dismal belief that the laws of nature respond to wailings and incantations.

By the time I was sixteen I had read many books and I had become a freethinker.

Intellectual freedom is essential -- freedom to obtain and distribute information, freedom for open-minded and unfearing debate and freedom from pressure by officialdom and prejudices. Such freedom of thought is the only guarantee against an infection of people by mass myths, which, in the hands of treacherous hypocrites and demagogues, can be transformed into bloody dictatorship.

I am convinced that everything that is worth while in the world has been accomplished by the free, inquiring, critical spirit, and that the preservation of this spirit is more important than any social system whatsoever. But the men of ritual and the men of barbarism are capable of shutting up the men of science and silencing them forever.

Don't read a book and be a follower; read a book and be a student.

If you read, you can learn to think for yourself.

A thinking that approaches it objects openly, rigorously ... is also free toward its objects in the sense that it refuses to have rules prescribed to it by organized knowledge. It ... rends the veil with which society conceals them, and perceives them anew.

We should only endeavour to think and speak correctly ourselves, without wishing to bring others over to our taste and opinions.

No nation like the United States of America can continue to grow and be a strong nation if we are going to judge people because they disagree with our agenda rather than the content of their statements. We have to be critical thinkers. We have to be analytical. We should understand facts from emotion.