How did Adam Smith explain the human tendency to trade and exchange?

The Scottish philosopher Adam Smith explained the human tendency to trade and exchange as a natural, inherent propensity rather than a result of deliberate foresight or wisdom.1

In his seminal work, An Inquiry into the Nature and Causes of the Wealth of Nations, Smith identified this "propensity to truck, barter, and exchange one thing for another" as the fundamental driver behind the division of labour. By specializing in specific tasks, individuals can significantly increase their productivity, which in turn facilitates the growth of national wealth.12

Smith viewed this behavior as a core element of human nature that allows complex economic structures to emerge from individual interactions. While he often described economic agents as acting in their own self-interest, he clarified that this does not imply selfishness; rather, it reflects individuals responding to their local circumstances, knowledge, and personal concerns. Ultimately, this natural inclination toward exchange serves as the foundation for the market mechanisms that coordinate supply and demand, fostering economic development when not inhibited by restrictive monopolies or government interference.12