The snake begged the frog for a ride across the stream.
The frog expressed fear, but the snake reassured him, pointing out that should the snake bite the frog then both would die.
The frog agreed. And mid-stream, the snake bit the frog.
“Why did you do that?” asked the frog, “Now we’ll both die.” The snake just smiled.
“I’m sorry,” he said, “but I’m a snake.”