Antoine Louis Claude Destutt, comte de Tracy (1754 – 1836) was a French Enlightenment aristocrat and philosopher who coined the term "ideology".
Destutt de Tracy was the last eminent representative of the sensualistic school which Condillac founded in France upon a one-sided interpretation of Locke. In full agreement with the materialist views of Cabanis, de Tracy pushed the sensualist principles of Condillac to their most necessary consequences. While the attention of Cabanis was devoted mostly to the physiological side of man, Tracy's interests concerned the then newly determined "ideological," in contrast to "psychological," sides of humanity. His grounding notion of ideology, he frankly stated, fell as "a part of zoology" (biology). The four faculties into which de Tracy divides the conscious life—perception, memory, judgment, volition—are all varieties of sensation. Perception is sensation caused by a present affection of the external extremities of the nerves; memory is sensation caused, in the absence of present excitation, by dispositions of the nerves which are the result of past experiences; judgment is the perception of relations between sensations, and is itself a species of sensation, because if we are aware of the sensations we must be aware also of the relations between them; and volition he identifies with the feeling of desire, and is therefore included as a type of sensation.
Considered for the influences of his philosophy, de Tracy minimally deserves credit for his distinction between active and passive touch, which ultimately fed the development of psychological theories of muscular sense. His account of the notion of external existence, as it derived not from pure sensation, but from the experience of action on the one hand and resistance on the other, stands in this light to be compared with the works of Alexander Bain and later psychologists.
His chief works are the five-volume Eléments d'idéologie (1817–1818), the first volume of which was presented as "Ideology Strictly Defined," and which completed the arguments made in earlier completed monographs; Commentaire sur l'esprit des lois de Montesquieu(1806), and Essai sur le génie, et les ouvrages de Montesquieu (1808). The fourth volume of the Eléments d'idéologie the author regarded as the introduction to a second section of the planned nine-part work, which he titled Traité de la volonté (Treatise on the Will and Its Effects). When translated into English, editor Thomas Jefferson retitled the volume A Treatise on Political Economy, which obscured the aspects of Tracy's concern not with politics, but with far more basic questions of will, and the possibility of understanding the conditions of its determinations.
Tracy advanced a rigorous use of deductive method in social theory, seeing economics in terms of actions (praxeology) and exchanges (catallactics). Tracy's influence can be seen both on the Continent, particularly on Stendhal, Augustin Thierry, Auguste Comte, and Charles Dunoyer, and in America, where the general approach of the French Liberal School of political economy competed evenly with British classical political economy well until the end of the 19th century, as evidence in the work and reputation of Arthur Latham Perry and others. In his political writings, Tracy rejected monarchism, favoring the American republican form of government. This republicanism, as well as his advocacy of reason in philosophy and laissez-faire for economic policy, lost him favor with Napoleon, who turned Tracy's coinage of "ideology" into a term of abuse; Karl Marx followed this vein of invective to refer to Tracy as a "fischblütige Bourgeoisdoktrinär"—a "fish-blooded bourgeois doctrinaire."
Thomas Jefferson, on the other hand, thought highly enough of Destutt de Tracy's work to ready two of his manuscripts for American publication. In his preface to the 1817 publication, Jefferson wrote, "By diffusing sound principles of Political Economy, it will protect the public industry from the parasite institutions now consuming it. . . ."