The Encyclopédistes (French: [ɑ̃siklɔpedist]) (also known in British English as Encyclopaedists,[1] or in U.S. English as Encyclopedists) were members of the Société des gens de lettres, a French writers' society, who contributed to the development of the Encyclopédie from June 1751 to December 1765 under the editors Denis Diderot and Jean le Rond d'Alembert, and only Diderot from 1765 to 1772.
Moreover, the sporadic research into the quotations, borrowings, and plagiarisms in the Encyclopédie – the illustrations as well as the text – illuminate a group of "indirect" collaborators.
From this mixture in the publication, we find the draft of a schoolboy next to a masterpiece.A machine-generated and incomplete list of authors sorted by number of posts can be found at the project ARTFL.
Diderot undertook the history of ancient philosophy, wrote the Prospectus and the System of Human Knowledge, and, with D'Alembert, revised all the articles.
In 1752 d'Alembert, who was tired of the mocking, cries of indignation, and religious persecution against the Encyclopédie, retired from the encyclopedic undertaking.