- "Nothing is lost, nothing is created, everything is transformed."
- ―Lavoisier's Law.[src]
Antoine-Laurent de Lavoisier (1743 – 1794) was a French nobleman and chemist, who made significant contributions to the science of combustion, including the identification of oxygen and hydrogen, and his pioneering work on the list of elements. He is consequently considered to be the "father of modern chemistry" in popular culture.
In 1771, Lavoisier married Marie-Anne Pierrette Paulze when she was thirteen years old. Becoming his lab assistant, she played an important role in his scientific career; notably, she translated books from English to French, so her husband could further his scientific knowledge.
Lavoisier was also a supporter of new philosophical ideas and a new social order, calling for the creation of social insurance and retirement funds for the elderly, the abolition of all forced work for peasants, as well as freedom of trade. In 1775, he began to serve on the Gunpowder Commission, which greatly improved the quality of France's munitions.
Having become an ally of the Assassins at some point, Lavoisier developed a poisonous smoke bomb for the Parisian Brotherhood during the French Revolution. However, while out on a walk, he was abducted by followers of Jean-Paul Marat, and the formula was stolen. Fortunately, the Assassin Arno Dorian had been alerted to Lavoisier's disappearance and managed to rescue him from his kidnappers, following which he recovered the stolen formula.
Lavoisier later contacted Arno again, asking the Assassin to rescue Pierre-Simon Laplace, an astronomer and mathematician who had been placed under house arrest. Arno did as requested and managed to free Laplace from his oppressors.
Having been accused of selling gunpowder outside of France by Marat, Lavoisier eventually fell afoul of the radical revolutionaries and was declared a traitor by the National Convention for his former ties to the Ferme Générale, a private tax-collecting system under the monarchy. Arrested, he was sent to the Maison Nationale de Sûreté and from there, to the guillotine in 1794, having been informed that "the Republic needed neither scientists nor chemists".
Following Lavoisier's death, Madame Lavoisier fought to preserve Antoine's legacy as a scientist, and compiled his notes and memoirs for publication. The Helix database credited Antoine Lavoisier as the one who could best explain the world until the arrival of Einstein.