This episode explores how trade transformed human society from isolated groups into interconnected civilizations. It begins with the instinct to exchange — how early humans bartered goods like obsidian, salt, and tools long before the invention of money or writing. As agriculture created surpluses, trade became organized through village markets that relied on trust and fairness, leading to innovations like standardized weights, seals, and contracts. The story expands to global scale with the rise of trade routes such as the Silk Road, which spread not only goods but also religions, technologies, and ideas across continents. Empires used trade to gain power and wealth, and later, industrialization turned exchange into global commerce. Finally, the episode reflects on today’s digital marketplaces and the way algorithms, cryptocurrencies, and online transactions continue to test humanity’s oldest commodity — trust.