If such a thing had happened once, it must surely have happened many times in this galaxy of a hundred billion suns.
Interpretation
The quote suggests that extraordinary events in the universe are likely to recur, given the vastness of space and time.
Arthur C. Clarke's quote reflects on the immense scale of the universe, indicating that if a rare or remarkable event occurred once, it is plausible it has occurred multiple times throughout the cosmos. It invites contemplation about the possibilities of life and experiences in a galaxy with such a phenomenal number of stars, encouraging an appreciation for the complexity and mystery of the universe.
In practice
During a lecture about astronomy, one could use this quote to emphasize the vast possibilities in the universe.
Nowhere in space will we rest our eyes upon the familiar shapes of trees and plants, or any of the animals that share our world. Whatsoever life we meet will be as strange and alien as the nightmare creatures of the ocean abyss, or of the insect empire whose horrors are normally hidden from us by their microscopic scale.
As our own species is in the process of proving, one cannot have superior science and inferior morals. The combination is unstable and self-destroying.
It has yet to be proven that intelligence has any survival value.
The best measure of a man's honesty isn't his income tax return. It's the zero adjust on his bathroom scale.
It was the mark of a barbarian to destroy something one could not understand.
My favorite definition of an intellectual: 'Someone who has been educated beyond his/her intelligence'.
The prediction of nuclear winter is drawn not, of course, from any direct experience with the consequences of global nuclear war, but rather from an investigation of the governing physics.
But it will be found... that one universal law prevails in all these phenomena. Where two portions of the same light arrive in the eye by different routes, either exactly or very nearly in the same direction, the appearance or disappearance of various colours is determined by the greater or less difference in the lengths of the paths.
We've all been sick; we're all afraid of infection. I think the easiest application to help people understand what quorum sensing is and why it's important to study is to tell them that if we could make the bacteria either deaf or mute, we could create new antibiotics.
The works of Lavoisier and his associates operated upon many of us at that time like the Sun's rising after a night of moonshine: but Chemistry is now betrothed to the Mathematics, and is in consequence grown somewhat shy of her former admirers.
Measure what is measurable, and make measurable what is not so.
Well, biology today as I see it has an amiable look - quite different from the 19th-century view that the whole arrangement of nature is hostile, 'red in tooth and claw.' That came about because people misread Darwin's 'survival of the fittest.'
Subscribe for the occasional hand-picked quote. No noise.