20 Inspiring Carl Sagan Quotes 25 Years After the Astronomer's Death

Carl Sagan, the beloved American astronomer, philosopher and educator, continues to shed light, 25 years after his death on December 20, 1996, on the state of society, politics, and our species' place in the universe.

An intellectual titan, Sagan also had an inimitable talent for making extraordinary concepts accessible to ordinary people and using everyday analogies to explain lofty insights, making all who read his words or heard his voice feel simultaneously invaluable and absurdly insignificant.

In a tribute to her late husband, scientist Ann Druyan said "the rest of us still struggle to catch up with him" a quarter of a century after his death, and that his ideas and concerns have become "more influential" over time.

He was passionately and repeatedly voicing his concerns over the state of the environment decades before it gained any mainstream traction, and he was also a firm advocate for equality, open dialogue, and curiosity.

In an effort to celebrate his life and his wisdom, Twitter users are sharing some of Sagan's most insightful and inspiring quotes online.

• "I strongly dislike the notion that if things get absolutely rotten here, we can run away to somewhere else. I think it's a silly idea on economic and on moral grounds. Nevertheless, it's true, in my opinion, that the maturity of the human species will be connected with our ability to leave the earth, our mother, and seek our fortune in the galaxy... but not to abandon the earth, by any means. If we don't put our house in order, we'll never be able to explore the cosmos."
• "The universe is a pretty big place. If it's just us, seems like an awful waste of space."
• "The nuclear arms race is like two sworn enemies standing waist deep in gasoline, one with three matches, the other with five."
• "I have a foreboding of an America in my children's or grandchildren's time—when the United States is a service and information economy; when nearly all the manufacturing industries have slipped away to other countries; when awesome technological powers are in the hands of a very few, and no one representing the public interest can even grasp the issues; when the people have lost the ability to set their own agendas or knowledgeably question those in authority; when, clutching our crystals and nervously consulting our horoscopes, our critical faculties in decline, unable to distinguish between what feels good and what's true, we slide, almost without noticing, back into superstition and darkness."
• "If you wish to make an apple pie from scratch, you must first invent the universe."
• "For small creatures such as we, the vastness [of the universe] is made bearable only through love."
• "After the Earth dies some 5 billion years from now, after it's burned to a crisp, or even swallowed by the Sun, there will be other worlds and stars coming into being—and they will know nothing of a place once called Earth."
• "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."
• "[...]preserve and cherish the pale blue dot, the only home we've ever known."
• "One of the saddest lessons of history is this: If we've been bamboozled long enough, we tend to reject any evidence of the bamboozle. We're no longer interested in finding out the truth. The bamboozle has captured us. It's simply too painful to acknowledge, even to ourselves, that we've been taken. Once you give a charlatan power over you, you almost never get it back."
• "Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves."
• "You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep-seated need to believe."
• "In science it often happens that scientists say, 'You know, that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again [...] I cannot recall the last time something like that happened in politics or religion."
• "We are bathing in mystery and confusion... That will always be our destiny. The universe will always be much richer than our ability to understand it."
• "Science is a way of thinking much more than it is a body of knowledge."
• "Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every 'superstar,' every 'supreme leader,' every saint and sinner in the history of our species lived there—on a mote of dust suspended in a sunbeam."
• "The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff."
• "The cosmos is within us. We are made of star-stuff. We are a way for the universe to know itself."
• "Our passion for learning [...] is our tool for survival."
• "The Earth is a very small stage in a vast cosmic arena. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot."