Pierre Eugène Marcellin Berthelot  FRS FRSE (25 October 1827 – 18 March 1907) was a French chemist and politician noted for the Thomsen-Berthelot principle of thermochemistry. He synthesized many organic compounds from inorganic substances, providing a large amount of counterevidence to the theory of Jöns Jakob Berzelius that organic compounds required organisms in their synthesis. He is considered as one of the greatest chemists of all time. He gave all his discoveries not only to the French government but to humanity.