He was best known for his discovery of the law of constant composition in 1794, stating that chemical compounds always combine in constant proportions.

Both Proust and Joyce record the ways in which human perspectives can be transformed. The second son of Joseph Proust, an apothecary, and Rosalie Sartre, Proust received his early education under the supervision of his godparents and continued it at the local Oratorian collège.He was then apprenticed to his father, to study pharmacy and to succeed him.

In Portrait, Stephen Dedalus is constantly undergoing epiphanies, but their effects are transitory: the new synthetic complex quickly falls apart. PROUST, JOSEPH LOUIS (b..Angers, France, 26 September 1754; d.Angers, 5 July 1826) chemistry.. Joseph-Louis Proust, also known as Luis Proust, (born Sept. 26, 1754, Angers, France—died July 5, 1826, Angers), French chemist who proved that the relative quantities of any given pure chemical compound’s constituent elements remain invariant, regardless of the compound’s source. “Marcel Proust, Selected Letters: 1910-1917”, HarperCollins Publishers Ltd 159 Copy quote There are mountainous, arduous days, up which one takes an infinite time to climb, and downward-sloping days which one can descend at full tilt, singing as one goes. Bio: Joseph Louis Proust was a French chemist. Proust's characters, by contrast, often achieve lasting changes of perspective.