I love a great teaching story. Often, a little story, fable, parable, or even a joke can make an important point in a succinct and memorable way.

And one of the most useful teaching stories is a story I heard told about a monkey. Now, it turns out there are many versions of this story, attributed to various people around the world—for instance, sometimes it’s told about a boy and hazelnuts—but here’s my version of that old story.

Once upon a time, there was a clever monkey who was exploring an outdoor market. He spotted a glass jar of bananas with a fairly narrow neck, and he darted over to snatch the bananas while the merchant’s back was turned. The monkey easily slid his hand to the bottom of the jar to grab the bananas, but with his hand gathered in a fist around them, he couldn’t pull withdraw his hand from the jar.

The only way to get free from the jar was to release the bananas and pull out his empty hand. But the greedy monkey wouldn’t let go, and the merchant was able to trap him in a net.

In some versions, the moral of the story is described as “Do not attempt too much at once.” I think the moral is, sometimes we need to recognize that something that we desire isn’t good for us, and we need to let it go in order to save ourselves.