“How It Happened” by Isaac Asimov
My brother began to dictate in his best oratorical style, the one which has the tribes hanging on his words.
“In the beginning,” he said, “exactly fifteen point two billion years ago, there was a big bang and the Universe–”
But I had stopped writing. “Fifteen billion years ago?” I said incredulously.
“Absolutely,” he said. “I’m inspired.”
“I don’t question your inspiration,” I said. (I had better not. He’s three years younger than I am, but I don’t try questioning his inspiration. Neither does anyone else or there’s hell to pay.) “But are you going to tell the story of the Creation over a period of fifteen billion years?”
“I have to,” said my brother. “That’s how long it took. I have it all in here,” he tapped his forehead, “and it’s on the very highest authority.”
By now I had put down my stylus. “Do you know the price of papyrus?” I said.
“What?” (He may be inspired but I frequently noticed that the inspiration didn’t include such sordid matters as the price of papyrus.)I said, “Suppose you describe one million years of events to each roll of papyrus. That means you’ll have to fill fifteen thousand rolls. You’ll have to talk long enough to fill them and you know that you begin to stammer after a while. I’ll have to write enough to fill them and my fingers will fall off. And even if we can afford all that papyrus and you have the voice and I have the strength, who’s going to copy it? We’ve got to have a guarantee of a hundred copies before we can publish and without that where will we get royalties from?”
My brother thought awhile. He said, “You think I ought to cut it down?”
“Way down,” I said, “if you expect to reach the public.”
“How about a hundred years?” he said.
“How about six days?” I said.
He said horrified, “You can’t squeeze Creation into six days.”
I said, “This is all the papyrus I have. What do you think?”
“Oh, well,” he said, and began to dictate again, “In the beginning– Does it have to be six days, Aaron?”
I said, firmly, “Six days, Moses.”