This isn't "by" me, it's a Chinese folktale that has evolved into a form of wordplay. Note that I'm just relaying the bits of this story I've heard, and perhaps it's more complex than what's here; if so, my apologies.
According to this story, there once was a man, who was a painter. He had just started on a painting of a horse, when he received a contract from a rich man to draw a tiger. Not wishing to start anew, the man decided to draw the head of a tiger onto the horse. His son saw what he was drawing, and came up to him.
"Father, what is that?" asked the boy.
"It's a horse," replied the father, not wishing to tell the boy that he was being sloppy.
So the boy later was outside, when he came across a tiger. Remembering what his father said, he tried to ride the tiger as a horse; and the tiger killed and ate the boy.
However, this is not the end of the tale. The painter's other son asked him what was on the canvas. The father said, "It's a tiger".
Remembering what his father said, this other son shot a horse with a bow and arrow, happening to kill a noble's prize stallion; thus the painter was driven bankrupt trying to make up to the nobleman for this deed.
The moral of the story is, don't do sloppy work.
The other moral of the story is, have smarter kids. Or alternatively, "Darwin always wins".
And even today, the story lives in. "Mama huhu" -- 马马虎虎-- now has come to mean "sloppy" or "so-so" in Chinese. So if someone asked me how I'm doing, I can use this term to mean "I'm doing so-so".