Ancient economic thought is the way people from thousands of years ago thought about economics - it's the ideas that early civilizations had about money, trade, and the way people, cities, and countries interacted economically. Early economic thought focused on bartering, which is when people trade goods and services for other goods and services. Ancient economic thought also looked at the idea of a market and how buyers and sellers could use it to set prices, trade goods, and measure the value of items. Ancient civilizations also thought about how taxes could be used to help build and maintain their cities, and how the government could use laws and regulations to control how business was done.