Carl Sagan

1934–1996 · American astrophysicist, cosmologist and author

Topics: science, learning, life, creativity

• With insufficient data it is easy to go wrong.

  — Carl Sagan

• We've tended in our cosmologies to make things familiar. Despite all our best efforts, we've not been very inventive.

  — Carl Sagan

• I believe that the extraordinary should certainly be pursued. But extraordinary claims require extraordinary evidence.

  — Carl Sagan

• Perhaps one per cent of the time, someone who has an idea that smells, feels and looks indistinguishable from the usual run of pseudoscience will turn out to be right.

  — Carl Sagan

• The best antidote for pseudoscience, I firmly believe, is science.

  — Carl Sagan

• It is postjudice. That is, not a judgement made before examining the evidence but a judgement made after examining the evidence.

  — Carl Sagan

• Suppose your father... walked into this room at the ordinary human pace of walking. And suppose just behind him was his father. How long would we have to wait before the ancestor who enters the now-open door is a creature who normally walked on all fours? The answer is a week.

  — Carl Sagan

• To me it is not in the least demeaning that consciousness and intelligence are the result of “mere” matter sufficiently complexly arranged; on the contrary, it is an exalting tribute to the subtlety of matter and the laws of Nature.

  — Carl Sagan

• Relativity does set limits on what humans can ultimately do. But the universe is not required to be in perfect harmony with human aspirations.

  — Carl Sagan

• Science is, at least in part, informed worship.

  — Carl Sagan

• Superstition is marked not by its pretension to a body of knowledge but by its method of seeking truth.

  — Carl Sagan

• It is all a matter of time scale. An event that would be unthinkable in a hundred years may be inevitable in a hundred million.

  — Carl Sagan

• There can be an infinite number of polygons, but only five regular solids.

  — Carl Sagan

• What an astonishing thing a book is.

  — Carl Sagan

• Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home.

  — Carl Sagan

• I believe our future depends powerfully on how well we understand this Cosmos in which we float like a mote of dust in the morning sky.

  — Carl Sagan

• It is important to distinguish between the amount of information and the quality of that information.

  — Carl Sagan

• A googolplex is precisely as far from infinity as is the number 1... no matter what number you have in mind, infinity is larger still.

  — Carl Sagan

• The neurochemistry of the brain is astonishingly busy, the circuitry of a machine more wonderful than any devised by humans. But there is no evidence that its functioning is due to anything more than the 1014 neural connections that build an elegant architecture of consciousness.

  — Carl Sagan

• At the molecular level, we are all virtually identical.

  — Carl Sagan