Carl Sagan

Carl Sagan
Carl Edward Saganwas an American astronomer, cosmologist, astrophysicist, astrobiologist, author, science popularizer, and science communicator in astronomy and other natural sciences. He is best known for his contributions to the scientific research of extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation. Sagan assembled the first physical messages sent into space: the Pioneer plaque and the Voyager Golden Record, universal messages that could potentially be understood by any extraterrestrial intelligence that might find...
NationalityAmerican
ProfessionScientist
Date of Birth9 November 1934
CityBrooklyn, NY
CountryUnited States of America
Absolute certainty will always elude us. We will always be mired in error. The most each generation can hope for is to reduce the error. . . .
'In his celebrated book, 'On Liberty', the English philosopher John Stuart Mill argued that silencing an opinion is "a peculiar evil." If the opinion is right, we are robbed of the "opportunity of exchanging error for truth"; and if it's wrong, we are deprived of a deeper understanding of the truth in its "collision with error." If we know only our own side of the argument, we hardly know even that: it becomes stale, soon learned by rote, untested, a pallid and lifeless truth.'
Indeed the reasoned criticism of a prevailing belief is a service to the proponents of that belief; if they are incapable of defending it, they are well advised to abandon it. This self-questioning and error-correcting aspect of the scientific method is its most striking property.
The fossil record implies trial and error, the inability to anticipate the future, features inconsistent with a Great Designer (though not a Designer of a more remote and indirect temperament.)
The near side of a galaxy is tens of thousands of light-years closer to us than the far side; thus we see the front as it was tens of thousands of years before the back. But typical events in galactic dynamics occupy tens of millions of years, so the error in thinking of an image of a galaxy as frozen in one moment of time is small.
They (i. e., the Pythagoreans ) did not advocate the free confrontation of conflicting points of view. Instead, like all orthodox religions, they practised a rigidity that prevented them from correcting their errors.
We are prodding, challenging, seeking contradictions or small, persistent residual errors, proposing alternative explanations, encouraging heresy. We give our highest rewards to those who convincingly disprove established beliefs.
Our perceptions are fallible. We sometimes see what isn't there. We are prey to optical illusions. Occasionally we hallucinate. We are error-prone.
The significance of our lives and our fragile planet is then determined only by our own wisdom and courage. We are the custodians of life's meaning. We long for a Parent to care for us, to forgive us our errors, to save us from our childish mistakes. But knowledge is preferable to ignorance. Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal.
We go about our daily lives understanding almost nothing of the world.
The secrets of evolution are death and time-the deaths of enormous numbers of lifeforms that were imperfectly adapted to the environment; and time for a long succession of small mutations.
When Kepler found his long-cherished belief did not agree with the most precise observation, he accepted the uncomfortable fact. He preferred the hard truth to his dearest illusions, that is the heart of science.
Science is merely an extremely powerful method of winnowing what's true from what feels good.
Our children long for realistic maps of the future that they can be proud of. Where are the cartographers of human purpose?