During this period he opened his salon to the philosophers Chaulieu, the Marquis of la Fare and Voltaire, and collaborated in the legislative labours of the chancellor d'Aguesseau.

[1] In March 1737 d'Argenson was appointed director of the censorship of books, in which post he showed sufficiently liberal views to gain the approval of writers—a rare thing in the reign of Louis XV.

In the spring of 1744 three armies were able to resume the offensive in the Netherlands, Germany and Italy, and in the following year France won the Battle of Fontenoy, at which d'Argenson was present.

[2] After the 1748 Treaty of Aix-la-Chapelle, other significant reforms included standardising the artillery, grouping Grenadiers into separate regiments, and setting up an officer training school, the École Militaire.

He was responsible for the arrangement of the promenade of the Champs Élysées and for the plan of the present Place de la Concorde.

Diderot and d’Alembert dedicated the Encyclopédie to him, and Voltaire, Charles-Jean-François Hénault, and Jean-François Marmontel openly visited him in his exile.