Condillac Defends Sensationalist Theory

In Treatise on the Sensations, Condillac defended a sensationalist theory of understanding, arguing that knowledge forms and develops solely through sensory experience. Condillac’s attribution of all human cognition to sensations had an enormous impact on contemporary and subsequent philosophers, especially in France and Italy.

Summary of Event

Under the influence of the English empiricist philosopher John Locke and in revolt against the deductive rationalism Rationalism of the French philosopher René Descartes, Étienne Bonnot de Condillac was convinced that all knowledge came from sensations. The belief that all human cognitions can be traced to their sensory sources is known as the sensationalist theory of knowledge. It was this theory that Condillac attempted to prove in his much celebrated Traité des sensations (1754; Condillac’s Treatise on the Sensations, Condillac’s Treatise on the Sensations (Condillac)[Condillacs Treatise on the Sensations] 1930). By drawing on a marble statue as a model, Condillac provided an ingenious genetic account of how people come to acquire knowledge. He argued that knowledge starts with the sense of smell alone, that other senses add to the picture, and that only the sense of touch can create a conception of a world external to the self. [kw]Condillac Defends Sensationalist Theory (1754)
[kw]Theory, Condillac Defends Sensationalist (1754)
[kw]Sensationalist Theory, Condillac Defends (1754)
Epistemology; and sense experience[sense experience]
[g]France;1754: Condillac Defends Sensationalist Theory[1400]
[c]Philosophy;1754: Condillac Defends Sensationalist Theory[1400]
Condillac, Étienne Bonnot de
Locke, John
Newton, Sir Isaac
Newton, Sir Isaac;influence on sensationalism[sensationalism]
[p]Descartes, René
Diderot, Denis
Tracy, Antoine-Louis-Claude Destutt de
Biran, Maine de
Cousin, Victor

Condillac’s philosophical career could be conveniently divided into two consecutive segments, one developmental and the other original. In his first phase, Condillac was mainly engaged in developing the philosophical ideas of Locke concerning human understanding within a systematic structure inspired by the works of Sir Isaac Newton. Although Locke’s An Essay Concerning Human Understanding (1690) and Newton’s Philosophiae Naturalis Principia Mathematica (1687; The Mathematical Principles of Natural Philosophy, 1729; best known as the Principia) were already popular in France, and the two intellectual giants were greatly admired, it was Voltaire’s Lettres philosophiques (1734; originally published in English as Letters Concerning the English Nation, 1733; also as Philosophical Letters, 1961), extolling English civilization, especially Locke and Newton, and his Éléments de la philosophie de Newton (1738; The Elements of Sir Isaac Newton’s Philosophy, 1738) that had exercised the greatest influence on Condillac’s mind.

Voltaire’s exegeses clarified for Condillac the British empiricist, Empiricism experience-centered Experiential philosophy way of thinking that he had felt was lacking in Descartes. Locke’s meticulous tracing of ideas to their origin in experience, combined with Newton’s dazzling simplification of our understanding of terrestrial and celestial motion through his law of gravitation, had seized Condillac’s allegiance and imagination by 1740. Consequently, in his study of the human mind, Condillac wanted to elucidate certain basic cognitive concepts such as attention, judgment, and reasoning by analyzing them in terms of one type of “primary fact.” He was trying to forge a Newtonian system to underpin a Lockean account of the mind.

Condillac’s Essai sur l’origine des connaissances humaines (1746; An Essay on the Origin of Human Knowledge: Being a Supplement to Mr. Locke’s “Essay on the Human Understanding,”
Essay on the Origin of Human Knowledge, An (Condillac) 1756) and Traité des systèmes (1749; A Treatise on Systems, Treatise on Systems, A (Condillac) 1982) were the products of this developmental stage of his life. Condillac argued that humans depend upon the body for their knowledge, specifically upon the interaction of external things with the body’s sense organs. People learn all they know by way of their bodies. There are two elements to every perception: an object acting on an organ and an impression that is triggered by that action. Judgment occurs when two impressions appear together. When there is a chain of such judgments, reasoning takes place. In this account, “understanding” refers to all the operations of the mind that arise automatically from impressions.

In the wake of these publications of the 1740’s, Denis Diderot, the great French Enlightenment figure and Condillac’s mentor, criticized Condillac in his Lettre sur les aveugles (1749; An Essay on Blindness, Essay on Blindness, An (Diderot) 1750) for the striking similarity of Condillac’s account to George Berkeley’s Berkeley, George subjective idealism. Idealism Diderot challenged Condillac to dissociate himself from Berkeley’s idealism, which asserted that all experience is a modification of the mind. This challenge from his mentor compelled Condillac to seek a proof for what he had previously merely assumed alongside Locke: that there is an external, material world responsible for causing the impressions that come to the mind and that the mind does not simply generate its own impressions without any external cause.

Condillac thus embarked upon the second and original phase of his philosophical profession, which culminated in the publication of his famous Treatise on the Sensations in 1754. The treatise was addressed to two problems: It attempted to show how impressions received by way of the bodily senses could give rise automatically, without reference to unobservable spirits or innate ideas, to all the mental operations. At the same time, it sought to defend the existence of an external, material world. The first task was familiar, but the second required a new approach.

Condillac ingeniously hypothesized a marble statue that was internally like a living human being. This hypothetical statue had a mind that was deprived of all ideas, and all of its senses were “closed,” but it was possible to open them one at a time and thereby to analyze the relationships between the various sensations. To avoid assuming the existence of an external world, Condillac chose to examine the sense of smell first, believing that odor involves no danger of being thought of as an image of an external object but is plainly a modification of the mind. Odor in Condillac’s analysis illustrates the familiar rise from mere perception to attention to memory. It also involves or induces an affective reaction, agreeableness or disagreeableness. From such experiential qualities, desires arise by a process similar to the way judgment and reasoning arise, and from these momentary desires, longer passions develop.

The question remains, however: How can the modification of the mind by a sense such as smell result in a belief in an external world? To prove such a belief valid, Condillac granted the statue the sense of touch. Other senses could not accomplish the task, but tactile sensation could, as a result of kinaesthesia. That is, by acquiring the sense of touch, the statue gained the ability to move itself mechanically by the confusedly felt contraction of its muscles. Thus, the statue first experienced double contact by, for example, touching its own chest with its hand. This sensation of double contact involved two feelings of solidity or resistance, one located in one place (the hand) and another located in another place (the chest), as well as two feelings of exclusion.

Condillac then had the statue press its hand against an object other than its own body. This object also excluded the hand from the object’s place, but now there was only one feeling of exclusion or resistance. By comparing double contact with single touch, the statue came to the awareness that there was an outward world, a world not felt from the inside but felt only as an external obstacle to the body.


The Treatise on the Sensations and Condillac’s subsequent application of its methods and conclusions to such other issues as language, liberty, morality, animals, and God heavily influenced other scholars. During his lifetime and for fifty years after his death, Condillac enjoyed fame and respect throughout Europe, and by the 1770’s his philosophy was being taught by all professors in Paris. He became the spokesman for his contemporaries as their professional philosopher, and eminent scientists such as Antoine-Laurent Lavoisier Lavoisier, Antoine-Laurent acknowledged their intellectual debt to Condillac’s methodology.

Condillac’s influence was most directly felt by the Idéologues, Idéologues (intellectual movement) members of a movement founded by Antoine-Louis-Claude Destutt de Tracy at the end of the eighteenth century. This movement designated a “science of ideas” Science;of ideas[ideas] devoted to empirical investigation of the origins of ideas and their relations, with the practical objective of achieving institutional reforms—beginning with the sweeping reform of the schools of France. The movement was initially very influential but was subsequently suppressed by Napoleon I.

Condillac’s thought was, however, subjected to an onslaught by Maine de Biran and Victor Cousin in the early decades of the nineteenth century. These philosophers accused Condillac of producing not an analysis of the way in which the human mind worked but an artificial reconstruction of how he imagined it worked. Although Condillac’s reputation never completely recovered from Biran and Cousin’s attack, in the latter part of the nineteenth century his thought enjoyed a new lease on life in the philosophies of Alexander Bain, John Stuart Mill, Herbert Spencer, and Hippolyte-Adolphe Taine. Also, Condillac has enjoyed continued popularity in Italy, where, from 1758 to 1767, he was tutor to the prince of Parma. His fame spread from Parma throughout most of Italy, and widespread admiration for his thought produced a steady stream of interpreters. There has been continued interest by scholars in Condillac’s psychology, metaphysics, and pedagogy.

Further Reading

  • Aarsleff, Hans, ed. and trans. Condillac: Essay on the Origin of Human Knowledge. New York: Cambridge University Press, 2001. A new translation of Condillac’s first work, which established him as the major empiricist thinker and advocate of sensationalism in the history of French philosophy.
  • Hine, Ellen McNiven. A Critical Study of Condillac’s “Traité des systèmes.” The Hague, the Netherlands: Martinus Nijhoff, 1979. A detailed examination of Condillac’s Treatise on Systems, which laid the groundwork for the Treatise on the Sensations.
  • Knight, Isabel F. The Geometric Spirit: The Abbé de Condillac and the French Enlightenment. New Haven, Conn.: Yale University Press, 1968. One of the most authoritative studies of Condillac in the English language.
  • O’Neal, John C. The Authority of Experience: Sensationalist Theory in the French Enlightenment. University Park: Pennsylvania State University Press, 1996. An investigation into the main ideas of Condillac and his fellow sensationalist philosophers and the ramifications of their sensationalist theories for education, ethics, and literature.
  • Pastore, Nicholas. Selective History of Theories of Visual Perception, 1650-1950. Oxford, England: Oxford University Press, 1971. A comparative account of Condillac’s sensationalist theory of vision from the scientific perspective.
  • Rosenfeld, Sophia. A Revolution in Language: The Problem of Signs in Late Eighteenth-Century France. Stanford, Calif.: Stanford University Press, 2001. Revisits Condillac’s conception of language and its impact on subsequent theories of language genesis and growth.
  • Yolton, John W., et al., eds. The Blackwell Companion to the Enlightenment. Malden, Mass.: Blackwell, 1995. A scholarly collection of philosophical articles on the ideas and intellectual impacts of Enlightenment figures, including Condillac.

Early Enlightenment in France

Hume Publishes A Treatise of Human Nature

Helvétius Publishes De l’esprit

Voltaire Publishes A Philosophical Dictionary for the Pocket

Publication of Holbach’s The System of Nature

Kant Publishes Critique of Pure Reason

Herder Publishes His Philosophy of History

Related Articles in <i>Great Lives from History: The Eighteenth Century</i><br />

Étienne Bonnot de Condillac; Denis Diderot; David Hume; Antoine-Laurent Lavoisier; Voltaire. Sensationalism
Epistemology; and sense experience[sense experience]