The villagers were paid to catch monkeys, which they did in large numbers when the price was low. As the supply decreased, the price was raised and they caught more. Eventually almost no monkeys remained. The man's assistant then told the villagers he would sell them the remaining monkeys at a lower price than the man was offering, letting the villagers profit by reselling to the man. The villagers bought all the monkeys, and were then left with many monkeys but no way to profit further from the scheme.