Destutt de Tracy's 'Treatise on the Will and its Effects', which he announced in 1805 after finishing the 'Logic,' was published in 1815 as the second section of the 'Eléments d'idéologie'. An addendum to the first section, the fourth part of the 'Eléments d'idéologie' dealing with practical philosophy and social theory and the unfinished fifth part on passion, morality and love are compiled in one volume. In 1823, this volume was given the title 'Traité d'économie politique', which was consistent with the American translation by Thomas Jefferson, published in 1818 as 'Treatise on Political Economy'. The main subjects of the 'Treatise on the Will' are the ideas of personality, human needs and means, wealth and deprivation, liberty and constraint, rights and obligations which arise from faculty of willing. This work also deals with social theory under the heading of »economy.«