Carl Edward Sagan was an American astronomer, cosmologist, astrophysicist, astrobiologist, author, science popularizer, and science communicator in astronomy and other natural sciences.
Sagan published more than 600 scientific papers and articles and was an author, co-author, or editor of more than 20 books. Sagan advocated scientific skeptical inquiry and the scientific method, pioneered exobiology, and promoted the Search for Extra-Terrestrial Intelligence (SETI). These are 29 beautiful thoughts from the scientist Carl Sagan.
Extraordinary claims require extraordinary evidence. - Carl Sagan
Extinction is the rule. Survival is the exception. - Carl Sagan
If you wish to make an apple pie from scratch, you must first invent the
universe. - Carl Sagan
A celibate clergy is an especially good idea, because it tends to suppress any
hereditary propensity toward fanaticism. - Carl Sagan
For small creatures such as we the vastness is bearable only through love. -
Carl Sagan
We are like butterflies that flutter for a day and think it is forever. - Carl
Sagan
Absence of evidence is not evidence of absence. - Carl Sagan
It's been said that astronomy is a humbling and, I might add, a
character-building experience. - Carl Sagan
Most of the people that I deal with are human. So I've had a lot of experience
with that. - Carl Sagan
We're in very bad trouble if we don't understand the planet we're trying to
save. - Carl Sagan
The universe is a pretty big place. If it’s just us, seems like an awful waste
of space. - Carl Sagan
When you make the finding yourself – even if you’re the last person on Earth
to see the light – you’ll never forget it. - Carl Sagan
The universe seems neither benign nor hostile, merely indifferent. - Carl
Sagan
The universe is not required to be in perfect harmony with human ambition. -
Carl Sagan
I can find in my undergraduate classes, bright students who do not know that
the stars rise and set at night, or even that the Sun is a star. - Carl Sagan
Every one of us is, in the cosmic perspective, precious. If a human disagrees
with you, let him live. In a hundred billion galaxies, you will not find
another. - Carl Sagan
The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the
carbon in our apple pies was made in the interiors of collapsing stars. We are
made of star stuff. - Carl Sagan
Imagination will often carry us to worlds that never were, but without it we
go nowhere. - Carl Sagan
It pays to keep an open mind, but not so open your brains fall out. - Carl
Sagan
We can judge our progress by the courage of our questions and the depth of our
answers, our willingness to embrace what is true rather than what feels good.
- Carl Sagan
It is far better to grasp the universe as it really is than to persist in
delusion, however satisfying and reassuring. - Carl Sagan
A celibate clergy is an especially good idea, because it tends to suppress any
hereditary propensity toward fanaticism. - Carl Sagan
All of the books in the world contain no more information than is broadcast as
video in a single large American city in a single year. Not all bits have
equal value. - Carl Sagan
The universe is not required to be in perfect harmony with human ambition. -
Carl Sagan
The brain is like a muscle. When it is in use we feel very good. Understanding
is joyous. - Carl Sagan
We’ve arranged a civilization in which most crucial elements profoundly depend
on science and technology. - Carl Sagan
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