It is not easy to see how the more extreme forms of nationalism can long survive when men have seen the Earth in its true perspective as a single small globe against the stars.
Sometimes when I’m in a bookstore or library, I am overwhelmed by all the things that I do not know. Then I am seized by a powerful desire to read all the books, one by one.
You can’t have it both ways. You can’t have both free will and a benevolent higher power who protects you from yourself.
The phenomenon of UFO doesn’t say anything about the presence of intelligence in space. It just shows how rare it is here on the earth.
The object of teaching a child is to enable the child to get along without the teacher. We need to educate our children for their future, not our past...
One theory which can no longer be taken very seriously is that UFOs are interstellar spaceships.
The realisation that our small planet is only one of many worlds gives mankind the perspective it needs to realise sooner that our own world belongs to all its creatures.
Now, before you make a movie, you have to have a script, and before you have a script, you have to have a story; though some avant-garde directors have tried to dispense with the latter item, you’ll find their work only at art theaters.
There is the possibility that humankind can outgrow its infantile tendencies, as I suggested in Childhood’s End. But it is amazing how childishly gullible humans are.
It was one thing to have guessed it, another to have had that guess confirmed beyond possibility of refutation.
Isaac Asimov is, in reality, based on something I had invented a few years previously.
The person one loves never really exists, but is a projection focused through the lens of the mind onto whatever screen it fits with least distortion.
Astronomy, as nothing else can do, teaches men humility.
The exploration of the planets is now closer to us in time than the exploration of Africa by Stanley and Livingstone.
Once you can reproduce a phenomenon, you are well on the way to understanding it.
Those meaningless and unanswerable questions the minds keep returning to, like a tongue exploring a broken tooth.
Training was one thing, reality another.
When the Sun shrinks to a dull red dwarf, it will not be dying. It will just be starting to live and everything that has gone before will merely be a prelude to its real history.
The only real problem in life is what to do next.
When all else failed, you had to rely on eyeball intrumentation.