The story goes that one day a woman was walking through the woods in the middle of the winter when she hears a rattle by her feet and looks down to see a rattlesnake. She jumps back, and the snake says "Please, I'm dying of the cold. Just pick me up and carry me in your coat to keep me warm."

Naturally she says "No, I can't do that. You'll bite me." But the rattlesnake begs and pleads and promises, until finally she relents and picks up the snake and tucks it in her jacket.

No sooner has it curled up than it lifts its head and bites her. The woman screams and throws the snake away, demanding to know why he did it. The snake just said "You knew what I was when you picked me up."