My Dad always substituted this Fable of the Snake for the classic "I told ya so" when I was growing up ;).
Many years ago, Indian youths would go away in solitude to prepare for manhood. One such youth hiked into a beautiful valley, green with trees, bright with flowers. There he fasted. But on the third day, as he looked up at the surrounding mountains, he noticed one tall rugged peak capped with dazzling snow.
I will test myself against that mountain, he thought. He put on his buffalo hide shirt, threw his blanket over his shoulders and set off to climb the peak
When he reached the top he stood at the rim of the world. He could see forever, and his heart swelled with pride. Then he heard a rustle at his feet, and looking down, he saw a snake. Before he could move, the snake spoke: ‘I am about to die, said the snake. "It is too cold for me up here and I am freezing. There is no food and I am starving. Put me under your shirt and take me down to the valley."
"No," said the youth. "I am forewarned, I know your kind. You are a rattlesnake. if pick you up, you will bite, and your bite will kill me."
"Not so," said the snake. "I will treat you differently. If you will do this for me, you will be special. I will not harm you."
The youth resisted awhile, but this was a very persuasive snake with beautiful markings. At last the youth tucked it under his shirt and carried it down to the valley. There be laid it gently on the grass, when suddenly the snake coiled, rattled and leapt, biting him on the leg.
"But you promised," cried the youth.
‘You knew what I was when you picked me up," said the snake as it slithered away.