Lavoisier considered that it was in founding the new chemistry that he gave his measure and history has largely ratified his self-estimate, according him the leading role that Isaac Newton played in physics, Charles Darwin in evolutionary biology, Albert Einstein in relativity, and Niels Bohr in quantum mechanics. All were prime movers in transformations of a scope that, as if anticipating political events, Lavoisier called a revolution in his science. This revolution includes the replacement of phlogiston by oxygen in the theory of combustion, the adoption of the systematic nomenclature in use ever since, the dependence on the principle of conservation of matter, the rigorously quantitative mode of analysis. Due weight must be given to the importance of his study of respiration both for physiology and for the early history of organic chemistry. But science is always a collective enterprise, and the parts of others, of predecessors, associates, and opponents, must be explained; here we have the whole cast, French, British, and European, and not merely the protagonist, the_ultimately tragic protagonist. Putting matters in perspective does not entail any belittling of Lavoisier's stature nor any subordination of the content of his science to the social and political context. Still, the overall story of the chemical revolution is familiar, and it is mainly in the account of Lavoisier's further concerns that new ground can be explored. Beyond the mere facts of his having been a partner in the Tax Farm, an administrator of the Gunpowder Service, and a model farmer, little has been known of how Lavoisier actually spent his days. As a rule, chemistry occupied only the hours before breakfast and in the evenings.

For the rest, his life was that of a financier, economist, and liberal administrator, a "grand commis d'état." (See Jean-Pierre Poirier. Lavoisier Chemist, Biologist, Economist, Philadelphia: Pennsylvania University Press, 1996). No mere investor in the Tax Farm, Lavoisier had direct responsibility for specific operations and for setting broad policy. Its practices, if not formally corrupt, do appear invidious enough to make the odium it incurred inevitable. Lavoisier's participation was both effective in general and self-serving in particular. Money was greatly important to him, as it is to many wealthy people, and finance a realm in which he made himself as expert as he did in science.

Lavoisier’s biography is economic history no less than history of science. In 1788 Lavoisier became chairman of the board of the Discount Bank, founded by Turgot in 1776, and forerunner of the Banque de France. His responsibilities there, together with agricultural experimentation on his own farm and a program of general agrarian reform developed in company with Pierre-Samuel Dupont de Nemours, led him into broad study of the measure of national wealth and productivity. Indeed, his involvement in the Revolution itself was as much that of financier and economist as of scientist. He served as a consultant on finance to the National Assembly in 1790-91 and a commissioner of the Treasury from April 1791 until February 1792. Lavoisier's success in administering the service, and his failure to persuade the Assembly to adopt sound fiscal policy, offer an instructive instance of the interplay of expertise with politics in revolutionary circumstance. He was very bad at politics: "This piece of writing will be as cool as reason," he wrote in the preamble to his estimate of the state of national finances in January 1792, a season of intense political heat.

In everything he did, his method was that of the balance sheet, carried over from quantitative chemical analysis wherein nothing is lost and the weight of the products of a reaction must equal the weight of the reagents. Even so, in the refining of crude saltpetre for the munitions industry, in the balancing of the cost of seed, manure, land, and labor against the value of agricultural produce, in the collection of taxes and transmission of the proceeds to the Crown, in overseeing the proportion of reserves to notes issued by the Discount Bank, in the double entry bookkeeping required of Treasury clerks, in his estimates of national wealth — in all these enterprises, meticulous attention to fact and rigorous control over quantity were the conditions of success. In prison awaiting trial and execution, he labored over his own accounts and over the final accounting of the Tax Farm. As Charles C. Gillispie once wrote, "the spirit of accountancy raised to genius, there is the hallmark of Lavoisier."