1840s in sociology

1840

• Pierre-Joseph Proudhon's What is Property? is published.

1841

• Auguste Comte published Volume 5 of The Course of Positive Philosophy: ''La Partie Historique De La Philosophie Sociale''

1842

• Auguste Comte publishes Volume 6 of The Course in Positive Philosophy: Le Complément De La Philosophie Sociale Et Les Conclusions Générales, ''completing the series.
• Auguste Comte's Sociologie Comme Instruction Affirmative is published
• Auguste Comte's Social Statics and Social Dynamics'' is published

1843

• Søren Kierkegaard's Either/Or is published in two volumes.
• John Stuart Mill's A System of Logic, Ratiocinative and Inductive is published in two volumes.

1844

• Friedrich Engels' Outline of A Critique of Political Economy is published
• Engels and Marx's The Holy Family is published
• Karl Marx's Economic and Philosophic Manuscripts are written.
• Max Stirner's The Ego and Its Own is published in German.

1845

• Friedrich Engels' Conditions of the Working Class in England is published

1846

• Marx and Engels' The German Ideology is written.
• Pierre-Joseph Proudhon's The System of Economic Contradictions or the Philosophy of Poverty is published
• Søren Kierkegaard's Two Ages: A Literary Review is published

1847

• Friedrich Engels' The Principles of Communism is written during October–November
• Karl Marx's The Poverty of Philosophy is published, a critique of Proudhon's 1846 work.

1848

• Engels and Marx's The Communist Manifesto is published
• Study group on the social question held attended by Frederic Le Play, Jean Reynaud, Lamartine, François Arago, Carnot, Lanjuinais, Tocqueville, Montalembert, Sainte-Beuve, Agénor de Gasparin, Abbé Dupanloup, Adolphe Thiers, Auguste Cochin, Charles Dupin and others

1849

• Søren Kierkegaard's The Sickness Unto Death is published.