Once upon a time, in the dim and distant past, a team of super-scientists from outer space set forth to find a suitable location for trials of a new life-form they had just created. In our own galaxy, they came across a moderately sized and reasonably stable star, one of whose planets orbited it at just the right distance to ensure the presence of liquid wateressential for the experiment. So they cheerily sprayed the planet with their new life-form, then proceeded on their way to check on other experiments in other galaxies.
A couple of billion years later, they returned to see how things were shaping up. After a thorough survey, however, opinions were divided.
Some team members said: "Cor, we made a right botch-up with that lot! It's true that one species has evolved with a sort of primitive intelligence, but all they use it for is finding new ways of slaughtering each other. Better wipe them outgiven time, they could infect the whole galaxy."
Other team members disagreed. "Oh, go ongive the little blighters a chance," they said. "They're not all bad, and they haven't been around all that long. Leave them for another billion years or so, then we can come back and see that they've been up to!"
Some discussion followed, but the optimists won the day and the team departed to continue their programme of routine inspections elsewhere.
As centuries went by, the optimists proved to have been right. Earth's people managed to gain a modicum of common sense; war and hatred became things of the past, the planet prospered, and they all lived happily together ever after.
"EH? WHAT?" I hear you shout. "Planet prospered, all lived happily togetheryou must be bonkers!"
Well, I did say it was a fairy tale, didn't I? And that's the way fairy tales end, innithappy ever after!