Louis Say

Say was born on 6 March 1774 in Lyon, France. His father, Jean-Etienne Say, was a Swiss-born silk trader. His mother was Françoise Brun de Castanet. He had a brother, Jean-Baptiste Say, who later became a classical liberal economist.

His paternal family were Protestants from Nîmes who were exiled in Geneva, Switzerland after the repeal of the Revocation of the Edict of Nantes in 1685. His paternal great-grandfather, also named Louis Say, moved first to Amsterdam, where he was a member of the Walloon Church, before settling in Geneva in 1694. His paternal grandfather, Jean Say, became a Swiss citizen.

Say began his career as a broker in Paris. He then moved to Abbeville, where he worked in the calico-whitening industry.

In 1813, Say asked Jules Paul Benjamin Delessert to recommend his cousin, Armand Delessert, who was the owner of a beetroot sugar refinery in Nantes. Shortly after, Say moved to Nantes and took over the refinery. After the government changed the law on tariffs in 1814, Say switched to using sugarcane in 1815. He later let his son Horace taken over the refinery. The company was known as Louis Say et Cie, later known as Béghin-Say, now a subsidiary of Tereos.

In 1832, with Constant Duméril, Say also opened a beetroot sugar factory in Ivry-sur-Seine, known as the "Raffinerie de Jamaïque" (English: "refinery from Jamaica").

Say married Constance Maressal in 1809. They had four sons: Gustave, Achille, Constant, and Louis Octave Say.

Say died on 6 May 1840 in Paris. He was sixty-six years old.