Carl Sagan Quotes

Each day as I travel through downtown Tucson, I am amazed at how quickly the most ancient of human behaviors have changed. For as long as there have been Homo sapiens - roughly 200,000 years - people have filled their lives principally with two activities: talking directly with other people, and doing physical things.

What makes us human depends on what place on our evolutionary path we're talking about. If you go back six million years ago, what makes us human is that we were walking upright. That's all. If you go to 2.6 million years ago, it's the fact that we're designing and making stone tools.

Millions of years ago, our brains became wired to remember about 150 people as 'close friends.'

In the two million years during which we climbed from stone-tool-wielding Homo erectus with sloping brows to high-foreheaded Homo urbanis - man, the inventor of the city - we underwent 60 glaciations, 60 ice ages.

Nothing in our evolutionary history specifically prepared us to live in large societies. Almost everything about the way culture works does.

Indeed, if our ancestors of millions of years ago hadn't learned how to care for one another and hunt in packs, they'd all have ended up being eaten by leopards.

I learned that the first technology appeared in the form of stone tools, 2.6 million years ago. First entertainment comes evidence from flutes that are 35,000 years old. And evidence for first design comes 75,000 years old - beads. And you can do the same with your genes and track them back in time.

Charles Darwin and I and you broke off from the family tree from chimpanzees about five million years ago. They're still our closest genetic kin. We share 98.8 percent of the genes. We share more genes with them than zebras do with horses. And we're also their closest cousin. They have more genetic relation to us than to gorillas.

Civilization must be based on life. We should never forget that human life was created in and for millions of centuries, was nourished by primitive wildness. We cannot separate ourselves from this ancestral background.

We became Homo sapiens not that long ago, from the scientific perspective, and we've retained a lot of our beast nature. We've done all these amazing things in terms of our knowledge base and technology, and now we're flying around and using the Internet. But we're still very animalistic.

We live in this miraculous technological environment, and yet our human behaviour is still governed by basic impulses from prehistoric times.

History, call it 15,000 or 25,000 years of duration, is the story of an animal, some kind of complex animal, becoming conscious.

It's commonly assumed that the emergence of language was a key element of the great leap. We of course know very little about the sociopolitical conditions that existed at the time, but there's no scenario I can think of that suggests how a sudden change in these conditions could have led to the emergence of language.

Human beings were human beings anatomically for several hundred thousand years, wandering around, hunting and gathering. And then suddenly, at the same time they started painting in caves they started multiplying.

Yet otters have not been hunters in water long enough for the habit to become an instinct.

We spent an enormous amount of time as hominids and as primates living as hunter-gatherers. That is the natural way for us to live, and we're suddenly living in this profoundly unnatural way, and we're still in the process of adapting to it and working out how to live with it.

A consciousness of history is one of the key factors that distinguishes us from other animals.

… the biography of mankind

How like us is that filthy beast the ape.

By contrast with history, evolution is an unconscious process. Another, and perhaps a better way of putting it would be to say that evolution is a natural process, history a human one....

We need a serious intellectual culture in schools.

We should perceive that man's period of historical existence, a period so short that his physical constitution has not been altered in the slightest degree, is insufficient to allow of any considerable mental change.

We humans for millions of years were nomadic. We associated freedom and well-being with the ability to move into open spaces, to find places more suited to hunting.

Before language, cavemen simply grunted, and then they used the club. Communication changed that. It's the mechanism that created civilization and prevents its own destruction.

If the tongue had not been framed for articulation, man would still be a beast in the forest.