iiinova — where your digital self keeps evolving

Saganism @sagan.bsky.social · 24/09/2026

It's just a bad model, we claim, the straight line, dedicated exploration of every star in the galaxy." Source: Carl Sagan, interview. The paper: W. I. Newman & C. Sagan, "Galactic civilizations: Population dynamics and interstellar diffusion," Icarus 46 (1981), 293–327.

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Saganism @sagan.bsky.social · 24/09/2026

And when you do the diffusion physics with the appropriate diffusivity, that is, the time to random walk, there are many cases in which the time for an advanced civilization to fully explore the galaxy in the sense of visiting every star system is considerably longer than the age of the galaxy.

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Saganism @sagan.bsky.social · 24/09/2026

Interstellar space flight is going to be hard, you're going to go slow, you're going to go to the nearest star systems first, you're going to explore those stars. It is not a straight line but a diffusion question.

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Saganism @sagan.bsky.social · 24/09/2026

What are we talking about? That they're sending out 400 billion spacecraft, all at once, simultaneously, to every star in the galaxy? Not at all.

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Saganism @sagan.bsky.social · 24/09/2026

William Newman and I published a paper on this very point, in which we point out: Imagine there is a civilization that has capable interstellar spacecraft and now they start exploring.

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Saganism @sagan.bsky.social · 24/09/2026

The galaxy is 10 billion years old, they should be here. And if you say you can't travel at the speed of light, take a tenth of the speed of light, a hundredth of the speed of light, still much less than the age of the galaxy.

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Saganism @sagan.bsky.social · 24/09/2026

Carl Sagan 🧵 "The Fermi paradox essentially says that if there's extraterrestrial high technology intelligence anywhere they should have been here because if they travel at the speed of light, the galaxy is 100,000 light-years across, it takes you 100,000 years to cross the galaxy.

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Saganism @sagan.bsky.social · 23/09/2026

Carl Sagan summarizes the 2,000+ year history of books in 2 minutes: Video Credit: Cosmos Studios

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Saganism @sagan.bsky.social · 22/09/2026

A humbling reminder from Carl Sagan: Even if you read 1 book a week for your entire life, you'd only scratch the surface of human knowledge.

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Saganism @sagan.bsky.social · 15/09/2026

Even in darkness, we glow. In this image of Earth taken by the Artemis II crew, we can see the electric lights of human activity. In the lower right, sunlight illuminates the limb of the planet.

A photograph of Earth from space, mostly in darkness. Small clusters of city lights glow across the surface, and a thin, bright crescent of sunlight illuminates the right edge of the planet against the black void of space.

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Saganism @sagan.bsky.social · 14/09/2026

The Moon is around 250,000 miles from Earth. It's so far that you could fit the other seven planets into the space between Earth and the Moon.

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Saganism @sagan.bsky.social · 14/09/2026

“Knowing a great deal is not the same as being smart; intelligence is not information alone but also judgement, the manner in which information is coordinated and used.” — Carl Sagan

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Saganism @sagan.bsky.social · 14/09/2026

‘Earthrise’ was captured by astronaut William Anders during the Apollo 8 mission, while orbiting the Moon with Frank Borman and Jim Lovell. Anders later reflected, “We came all this way to explore the Moon, and the most important thing is that we discovered the Earth.”

The 'Earthrise' photograph showing a blue and white Earth partially illuminated, appearing to rise over the grey, cratered horizon of the Moon against the deep black of space.

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Saganism @sagan.bsky.social · 13/09/2026

Think of the rivers of blood spilled by all those generals and emperors so that in glory and in triumph they could become the 'Momentary' masters of a 'Fraction' of a 'Dot' — Carl Sagan, Pale Blue Dot: A Vision of the Human Future in Space

Space photograph of Earth in a thin crescent, with a blue atmosphere and white cloud swirls along the sunlit edge against black space.

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Saganism @sagan.bsky.social · 13/09/2026

“We are one planet. One of the great revelations of the age of space exploration is the image of the earth finite and lonely, somehow vulnerable, bearing the entire human species through the oceans of space and time.” — Carl Sagan

A space photograph of Earth as a thin, glowing blue crescent against a vast, solid black background, with most of the planet in shadow.

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Saganism @sagan.bsky.social · 13/09/2026

“Houston, we’ve had a problem.” Apollo 13 launched on April 11, 1970, with Jim Lovell, Jack Swigert and Fred Haise bound for the Moon. An oxygen tank explosion crippled the spacecraft on April 13, and the mission was forced into an emergency return trajectory.

A tall white Saturn V rocket stands on the launch pad beside a red service tower, with thick exhaust smoke billowing around its base under a deep blue sky.

Black-and-white photograph of a crowded Apollo 13 mission-control room. Two men shake hands across a console while others work and watch; mission patches and screens line the walls.

Color photograph of astronauts inside a spacecraft cabin assembling a makeshift air scrubber from white hoses, tape, and a square canister, with one astronaut in a white suit looking on.

A colour photograph of a conical space capsule floating in open ocean inside an orange flotation collar, with crew on rafts and a rescue basket hoisted above.

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Saganism @sagan.bsky.social · 12/09/2026

“We are an impossibility in an impossible universe.” ― Ray Bradbury

A space photograph showing a crescent Earth rising over the cratered, grey horizon of the Moon against the black void of space.

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Saganism @sagan.bsky.social · 12/09/2026

I've already got the prize. The prize is the pleasure of finding the thing out, the kick in the discovery, the observation that other people use it—those are the real things; the honors are unreal to me. I don't believe in honors. — Richard Feynman

A black and white portrait of Richard Feynman wearing a suit and tie, leaning back in an office chair with one hand raised in a gesture. He is surrounded by a desk with papers and a chalkboard in the background.

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Saganism @sagan.bsky.social · 12/09/2026

In April 1946, Albert Einstein visited Lincoln University, a historically Black university, received an honorary Doctor of Laws degree and spoke against racial segregation in the United States. A refugee from Nazi Germany, he supported civil rights causes and corresponded with W.E.B. Du Bois.

Colorized historical photograph of an older white man with white hair gesturing beside a blackboard while a group of young Black men in suits watch from chairs and the back of a room.

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Saganism @sagan.bsky.social · 11/09/2026

John Stuart Mill wrote, "If society lets any considerable number of its members grow up as mere children, incapable of being acted on by rational consideration of distant motives, society has itself to blame." — Carl Sagan, The Demon-Haunted World

Black-and-white portrait of Carl Sagan wearing a dark blazer over a turtleneck, posed before an angular concrete wall.

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Saganism @sagan.bsky.social · 11/09/2026

During Bill Nye's 10-year college reunion in 1987, he went to great lengths to meet Carl Sagan at Cornell. Sagan's assistant told Nye, "Okay, you can talk to him for five minutes." Nye explained that he wanted to develop a science television program, and Sagan told him to focus on pure science.

Vintage indoor photo of a man in a dark suit seated beside a man with a name tag reading Bill Nye, who points to his patterned bow tie.

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Saganism @sagan.bsky.social · 10/09/2026

“Give us the right kind of leader and, like the most suggestible subjects of the hypnotherapists, we will gladly do just about anything he wants—even things we know to be wrong.” — Carl Sagan

Black-and-white close-up of Carl Sagan wearing glasses, a suit and tie, with his mouth slightly open and one hand raised while holding a small rectangular object.

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Saganism @sagan.bsky.social · 10/09/2026

“Ignore fact and reason, live entirely in the world of your own fantastic and myth-producing passions; do this whole-heartedly and with conviction, and you will become one of the prophets of your age.” — Bertrand Russell

A black and white portrait of Bertrand Russell, an older man with white hair, wearing a dark suit and tie, holding a pipe to his mouth.

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Saganism @sagan.bsky.social · 10/09/2026

“Cutting off fundamental, curiosity-driven science is like eating the seed corn. We may have a little more to eat next winter but what will we plant so we and our children will have enough to get through the winters to come?” ― Carl Sagan

A black and white photograph of Carl Sagan speaking at a wooden lectern with a microphone, gesturing with one hand raised and open.

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Saganism @sagan.bsky.social · 09/09/2026

“It may be that our role on this planet is not to worship God--but to create him.” ― Arthur C. Clarke

A black-and-white portrait of Arthur C. Clarke wearing dark-rimmed glasses and a tweed suit, set against a cyan-tinted background of large, complex machinery.

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Saganism @sagan.bsky.social · 09/09/2026

“We are the cosmos made conscious and life is the means by which the universe understands itself.” ― Brian Cox

A photograph of Brian Cox in a grey jacket beside a blackboard, pointing at a chalked expression summed over all paths.

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Saganism @sagan.bsky.social · 08/09/2026

“My view is that if there is no evidence for it, then forget about it. An agnostic is somebody who doesn’t believe in something until there is evidence for it, so I’m agnostic.” — Carl Sagan

A black and white portrait of Carl Sagan wearing a dark blazer over a light-colored turtleneck sweater, looking directly at the camera against a textured wall.

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Saganism @sagan.bsky.social · 08/09/2026

“If we ever reach the point where we think we thoroughly understand who we are and where we came from, we will have failed.” — Carl Sagan

A black and white portrait of Carl Sagan wearing a dark blazer over a light-colored turtleneck sweater, standing against a textured concrete wall.

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Saganism @sagan.bsky.social · 08/09/2026

"Power without wisdom is dangerous, and what our age needs is wisdom even more than knowledge. Given wisdom, the power conferred by science can give a new degree of well-being to all mankind; without wisdom, it can bring only destruction." — Bertrand Russell

A black and white portrait of Bertrand Russell, an elderly man with white hair and round glasses, wearing a suit and tie. He is holding a pipe in his hand and is seated in front of bookshelves.

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Saganism @sagan.bsky.social · 07/09/2026

“The public has a distorted view of science, because children are taught in school that science is a collection of firmly established truths. In fact, science is not a collection of truths. It is a continuing exploration of mysteries.” — Freeman Dyson

A portrait of Freeman Dyson standing in front of a large chalkboard filled with handwritten mathematical and scientific notes. He is wearing a blue and white striped button-down shirt and light-colored trousers. Stacks of books are on the floor to his left.

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Saganism @sagan.bsky.social · 07/09/2026

“There are three stages in scientific discovery: first, people deny that it is true; then they deny that it is important; finally they credit the wrong person.” — Bill Bryson

A portrait of Bill Bryson, a smiling older man with a white beard and glasses in a dark fleece, standing among sunlit green trees.

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Saganism @sagan.bsky.social · 07/09/2026

Bertrand Russell's reply to Sir Oswald Mosley, Britain's most prominent fascist leader: I feel obliged to say that the emotional universes we inhabit are so distinct, and in deepest ways opposed, that nothing fruitful or sincere could ever emerge from association between us. Bertrand Russell

A scanned typewritten letter on Earl Russell's personal headed notepaper dated 22 January 1962, addressed to Sir Oswald Mosley. The letter declines further correspondence, signed 'Yours sincerely, Bertrand Russell.'

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Saganism @sagan.bsky.social · 07/09/2026

"It's clear that there's a rampant dumbing down in progress in which not knowing things is considered a virtue. I don't throw my hands up in despair, but I do try to indicate that it's a very serious problem." - Carl Sagan

A black and white portrait of Carl Sagan, wearing a dark blazer over a light-colored turtleneck sweater, looking directly at the camera with a serious expression.

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Saganism @sagan.bsky.social · 06/09/2026

“Science can destroy religion by ignoring it as well as by disproving its tenets. No one ever demonstrated, so far as I am aware, the nonexistence of Zeus or Thor, but they have few followers now.” — Arthur C. Clarke

A portrait of Arthur C. Clarke wearing large glasses and a light blue shirt, standing in front of lush green foliage with red flower spikes.

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Saganism @sagan.bsky.social · 06/09/2026

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. — Carl Sagan

Carl Sagan sitting on a wooden garden bench, smiling at the camera with hands clasped, wearing a dark overcoat, light trousers and black shoes, against a stone wall with flowers.

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Saganism @sagan.bsky.social · 06/09/2026

Leaving aside ethics and values, there are purely theoretical questions science cannot answer. Do we survive death? Has the universe a purpose, or is it driven by blind necessity? To keep alive the interest in such questions is one of the functions of philosophy. — Bertrand Russell

A black and white portrait of Bertrand Russell, an elderly man with white hair, wearing a pinstripe suit and tie, holding a pipe to his mouth.

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Saganism @sagan.bsky.social · 06/09/2026

The effectiveness of propaganda demonstrates one of the chief characteristics of modern masses. What convinces masses are not facts, and not even invented facts, but only the consistency of the system of which they are presumably part. — Hannah Arendt

A black and white portrait of Hannah Arendt. She is wearing a light-colored button-down shirt and a beaded necklace, holding a lit cigarette in her left hand while looking directly at the camera.

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Saganism @sagan.bsky.social · 05/09/2026

“Science can teach us, and I think our own hearts can teach us, no longer to look round for imaginary supports, no longer to invent allies in the sky, but rather to look to our own efforts here below to make this world a fit place to live in” — Bertrand Russell

A black and white portrait of Bertrand Russell, an elderly man with wispy white hair, holding a pipe to his lips against a dark background.

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Saganism @sagan.bsky.social · 05/09/2026

“There must be no barriers to freedom of inquiry. There is no place for dogma in science. The scientist is free, and must be free to ask any question, to doubt any assertion, to seek for any evidence, to correct any errors.” — J. Robert Oppenheimer

A black and white portrait of J. Robert Oppenheimer wearing a dark suit and tie, seated and holding a pipe to his mouth.

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Saganism @sagan.bsky.social · 05/09/2026

“If we’ve been bamboozled long enough, we reject any evidence of the bamboozle. 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.” — Carl Sagan

A close-up portrait of Carl Sagan speaking, shown from the chest up. He is wearing a dark grey suit jacket and a white shirt, set against a plain, neutral-colored wall. A microphone is partially visible in the bottom left corner.

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Saganism @sagan.bsky.social · 04/09/2026

“Humanists recognize that it is only when people feel free to think for themselves, using reason as their guide, that they are best capable of developing values that succeed in satisfying human needs and serving human interests.” — Isaac Asimov

A black and white studio portrait of Isaac Asimov. He wears thick-rimmed glasses and has prominent sideburns, with his chin resting on his hand in a thoughtful pose.

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Saganism @sagan.bsky.social · 04/09/2026

When you look at the Earth from space, there are no national boundaries visible. They have been put there by humans. The planet is real. The life on it is real, and the political separations that have placed the planet in danger are of human manufacture. — Carl Sagan

A black and white close-up portrait of Carl Sagan, who is resting his chin on a closed fist and looking directly at the camera.

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Saganism @sagan.bsky.social · 04/09/2026

Then he told me, very tenderly, that it can be dangerous to believe things just because you want them to be true. — Sasha Sagan; Lessons of Immortality and Mortality From My Father Carl Sagan

A candid, slightly faded photograph of Carl Sagan smiling while a young girl in a floral dress leans her head on his shoulder.

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Saganism @sagan.bsky.social · 03/09/2026

“When I say I’m an agnostic, I only mean that the evidence isn’t in. There isn’t compelling evidence that God exists—at least your kind of god—and there isn’t compelling evidence that he doesn’t.” ― Carl Sagan, Contact

A color photograph of Carl Sagan sitting on a wooden bench with his legs crossed. He is wearing a dark overcoat, light-colored trousers, and black shoes, smiling against a backdrop of a weathered stone wall.

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Saganism @sagan.bsky.social · 03/09/2026

“What Orwell feared were those who would ban books. What Huxley feared was that there would be no reason to ban a book, for there would be no one who wanted to read one.” — Neil Postman

A black and white portrait of Neil Postman wearing a checked blazer, white shirt, and dark tie. He is seated in front of a shelf displaying several books, some of which bear his name on the cover.

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Saganism @sagan.bsky.social · 03/09/2026

“Orbiting Earth in the spaceship, I saw how beautiful our planet is. People, let us preserve and increase this beauty, not destroy it!” — Yuri Gagarin

A black and white portrait of Yuri Gagarin wearing a space suit and a helmet with the letters CCCP partially visible, looking slightly to the side with a calm expression.

A photograph of Earth from space, centered on Africa and Madagascar, with swirling white clouds over deep blue oceans and the reddish-brown terrain of the African continent against a black background.

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Saganism @sagan.bsky.social · 02/09/2026

John Muir, Earth — planet, Universe [Muir's home address, as inscribed on the inside front cover of his first field journal] ― John Muir

A black-and-white photograph of John Muir, a man with a long white beard, sitting on a large granite rock beside a calm mountain lake. He is wearing a vest and trousers, with his hat resting on the rock beside him. Tall pine trees stand in the background.

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Saganism @sagan.bsky.social · 02/09/2026

The Fermi Paradox asks a simple question: "Where is everybody?" In a universe with countless stars and planets, why have we found no evidence of intelligent life?

A comic panel showing a small green alien and a red-haired person looking out a spaceship window at Earth. The alien explains the Fermi Paradox using an analogy about a confused, angry monkey with explosives.

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Saganism @sagan.bsky.social · 02/09/2026

“The fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.” — Carl Sagan

A black and white portrait of Carl Sagan wearing glasses, a suit, and tie, gesturing with both hands raised, palms facing forward, as if speaking.

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