1,131 Quotes by Carl Sagan

Exponential increases in population will dominate any arithmetic increases, even those brought about by heroic technological initiatives, in the availability of food and resources, as Malthus long ago realized. While some industrial nations have approached zero population growth, this is not the case for the world as a whole.

The illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world.

I would expect a significant development and elaboration of language in only a few generations if all the chimps unable to communicate were to die or fail to reproduce. Basic English corresponds to about 1,000 words. Chimpanzees are already accomplished in vocabularies exceeding 10 percent of that number.

Thus we do not yet have experience with theadult language abilities of monkeys and apes. One of the most intriguing questions is whether a verbally accomplished chimpanzee mother will be able to communicate language to her offspring. It seems very likely that this should be possible and that a community of chimps initially competent in gesturallanguage could pass down the language to subsequent generations.

We sometimes hear of things that can travel faster than light. Something called 'the speed of thought' is occasionally proffered. This is an exceptionally silly notion especially since the speed of impulses through the neutrons in our brain is about the same as the speed of a donkey cart.

Advertising teaches people not to trust their judgment. Advertising teaches people to be stupid.

In all our searching, the only thing we've found that makes the emptiness bearable is each other.

Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring--not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive... If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds.

To live in the hearts we leave behind is to live forever.