The numbers of distinct human societies or nations, when our race is twice its present age, may be far greater than the total number of all the men who have ever lived up to the present time.
Arthur C. ClarkeI can never look now at the Milky Way without wondering from which of those banked clouds of stars the emissaries are coming. If you will pardon so commonplace a simile, we have set off the fire alarm and have nothing to do but to wait. I do not think we will have to wait for long.
Arthur C. ClarkeWe have to abandon the idea that schooling is something restricted to youth. How can it be, in a world where half the things a man knows at 20 are no longer true at 40 - and half the things he knows at 40 hadn't been discovered when he was 20?
Arthur C. Clarke