From the Revolution of 1830 he understood the gravity of the social upheaval and then devoted himself to studying the progress of working life and especially of the family, conducting an inquiry into 300 model families from 1820 to 1853 (*Les ouvriers européens*, 1855). From 1860 onwards, he broadened his outlook, fully entering into reformist action. The ideas contained in *Réforme sociale en France* (1867), in *Organisation du travail* (1870), in *La méthode sociale* (1879), and in many other works were applied by the Union de la paix sociale and propagated after 1881 by the journal *La réforme sociale*. His plan was above all moral: he reproached the Revolution with three great errors: that of man’s original perfection, of individual infallibility, and of absolute equality. The remedy he proposed consisted in restoring respect in three forms: respect for God and religion; respect for the father and obedience; respect for woman or moral chastity. Le P. was little favourable to associations: he awaited the reform of authority, which led him to paternalism.
His work was continued by two schools: the reforming work by the “École de la paix sociale” and the positive work of observation and research by the “École de la science sociale,” founded in 1885 by M. Demolins and by Abbé de Tourville.