As I approach my 90th birthday, my friends are asking how it feels like, to have completed 90 orbits around the Sun. Well, I actually don't feel a da… - Arthur C. Clarke

The dinosaurs disappeared because they could not adapt to their changing environment. We shall disappear if we cannot adapt to an environment that now contains spaceships, computers — and thermonuclear weapons.

It was the end of civilization, the end of all that men had striven for since the beginning of time. In the space of a few days, humanity had lost its future, for the heart of any race is destroyed, and its will to survive is utterly broken, when its children are taken from it.

There were other thinkers, Bowman also found, who held even more exotic views. They did not believe that really advanced beings would possess organic bodies at all. Sooner or later, as their scientific knowledge progressed, they would get rid of the fragile, disease-and-accident-prone homes that Nature had given them, and which doomed them to inevitable death. They would replace their natural bodies as they wore out — or perhaps even before that — by constructions of metal and plastic, and would thus achieve immortality.