Lavoisier and the Quantification of Chemistry

Abstract Dissatisfied with his predecessors’ metaphysical speculations regarding fundamental matter, the 18th-century chemist Antoine Lavoisier took chemistry in a different direction from that followed in the previous century. He did so by eschewing philosophical theorizations and by rendering chemistry an entirely empirical pursuit with quantifiable experimental results. According to Lavoisier, rather than speculating about the fundamental nature of matter, chemists should restrict themselves to identifying the final products of analysis and to regarding those products that could not be further analyzed as elementary substances. The reformed chemical nomenclature that Lavoisier proposed focused on reflecting the elementary composition of compound substances and, thus, on identifying the “simple substances” of which compound substances were composed. Lavoisier was thus able to codify a simple, coherent, and accurate compositional chemistry. His approach allowed him to identify 33 elements, thus taking the first and essential step in the direction of modern chemistry. In spite of the success of his approach, Lavoisier claimed that neither experience nor experimental observation could furnish proof that a substance was truly elementary. In fact, he regarded the analytical approach to identifying elements as provisional and his table of elements as open to revision, since he recognized that future and more sophisticated methods of analysis might succeed in further breaking down the substances on his list of elements. Lavoisier’s quantification of chemistry and his identification of chemical elements represented crucial turning points not only for chemistry but for the entire conceptual structure of science.