In a great forest, some woodcutters came one day to cut timber. They were splitting a thick tree trunk right down the middle. The work was half done. They wedged a wooden peg into the split to hold it open, then went off to eat their midday meal.
A monkey lived in that very forest. He was a restless, mischievous sort. When the woodcutters left, he hopped over to the tree. That peg stuck in the middle looked very strange to him.
'What on earth is this?' he wondered. Curiosity got the better of him. He climbed up and peered at the peg. Then he began to pull at it.
The moment the peg came free, the two halves of the tree trunk snapped back together. The monkey's leg was right in between. It was caught fast and hard.
The monkey cried out. He struggled. But the tree would not let go. The woodcutters were far away. There was no one to hear him.
When the woodcutters finally came back, they freed the monkey. But his leg was badly hurt.
Meddling with work that is not your own is never a good idea. The monkey pulled out that peg without thinking — and ended up trapped by his own doing.