Jean-Baptiste Say (French: [ʒɑ̃batist sɛ]; 5 January 1767 – 15 November 1832) was a liberal French economist and businessman who argued in favor of competition, free trade and lifting restraints on business. He is best known for Say's law—also known as the law of markets—which he popularized, although scholars disagree as to whether it was Say who first articulated the theory. Moreover, he was one of the first economists to study entrepreneurship and conceptualized entrepreneurs as organizers and leaders of the economy. He was also closely involved in the development of the École spéciale de commerce et d'industrie (ESCP), historically the first business school to be established.
Source : Wikipedia