La Mettrie, Julien Offray De

(b. Saint-Malo, France, 19 December 1709; d. Berlin, Germany, 11 November 1751)

medicine, physiology, psychology, philosophy of science.

The son of a prosperous textile merchant, La Mettrei studied medicine at the University of Paris from 1728 until 1733, when he transferred to Rheims to obtain the doctor’s degree. He completed his training after another year at Leiden under the renowned Hermann Boerhaave, whose influence on him was decisive. From 1734 on, La Mettrie practiced medicine in the Saint-Malo district. Toward the end of 1742, however, he left abruptly for Paris and soon thereafter embarked on the adventurous and harried career that lasted until his death. Between 1743 and 1746 he served as an army doctor in the War of the Austrian Succession. Meanwhile, his first philosophical work, Histoire naturelle de l’?me (1745), which expounded a materialistic theory of the “soul,” provoked a scandal and was officially condemned by the Paris Parlement. Despite this offense against orthodoxy, La Mettrie’s professional ability was apparently esteemed enough for him to be promoted to the post of medical inspector of the armies in the filed. But he imprudently turned, in La politique du médecin de Machiavel (1746), to ridiculing the incompetence, greed, and charlatanry of a gallery of prominent French physicians. This justified and successful attempt at medical satire was followed by La faculté vengée (1747) and his magnum opus in that vein, L'ouvrage de Pénélope, ou Machiavel en médecine (1748–1750).

La Mattrie’s combined attacks against religion and the medical profession made him so many powerful enemies that, in order to escape arrest and imprisonment, he exiled himself to Holland in 1747. But unable to avoid trouble for long, he published there his most notorious book, L’homme machine (1748), the outspoken materialism and atheism of which raised a storm of protest even among the relatively tolerant Dutch. Its author, now regarded by the public as the most daring and dangerous of the Philosophes, was forced to flee again, this time to the court of Frederick II of Prussia, where he was appointed a member of the Royal Academy of Sceiences, as well as reader and physician to the king. In this protected situation he continued to write tracts on scientific and philosophical subjects that shocked the conventional-minded. In particular his Discours sur le bonheur (1748), which denied that vice and virtue had any meaning within a deterministic view of human nature and, consequently, saw in remorse simply a morbid symptom to be got rid of, caused him (somewhat illogically) to be denounced as a debauched and cynical corrupter of morals. La Mettrie’s querulous and mocking temper embroiled him in constant polemics, often of a mystifying sort, with his various adversaries, the most notable of these being the physiologist Albrecht von Haller. Even his death became an occasion for controversy, when his detractors, advertising that he had died by an act of gluttony, represented this as proof of the practical hazards of materialism and of the certainly of God’s retribution.

La Mettrie’s main service to medicine was his advocacy and propagation of Boerhaave’s teaching. This he did by translating into French many of the master’s works, in some cases appending to them commentaries of his own. The following translations form the Boerhaavian corpus deserve mention: Systé sur les maladies vénériennes (Paris, 1735); Aphorismes sur la connaissanece et la cure des maladies (Rennes, 1738); Traité de la matiére médicale (Paris, 1739); Abrégé de la théorie chimique de la terre (Paris, 1741); and the monumental Institutions de médecine (Paris, 1743–1750), which included Haller’s lengthy and valuable notes. La Mettrie’s efforst to spread the lessons of Boerhaave had the positive result not only of proddint the rather sluggish medical science and practice in eighteenth-century France but also of bringing medical subject matter into the arena of philosophical discussion and intellectual history,. In this respect there were two aspects of Boerhaavian doctrine that the zeaous disciple was especially eager to have accredited by doctors and nondoctors alike. One was the emphasis on the empirical method and on clinical observation. The other was the aim of establishing medicine on as sound a theoretical basis as possible by linking it directly to anatomy, physiology, chemistry, and mechanics. La Mettrie thus became a leading expositor of the iatromechanistic philosophy of Boerhaave, to which he soon gave a ridical application quite unintended by his teacher.

It is regrettable that the Boerhaavian methodology did not play a more noticeable role in the four treatises, long since forgotten, that La Mettrie wrote on venereal disease, vertigo, dysentery, and asthma. His personal contribution to medicine remained on the theoretical rather than the practical plane. Nevertheless, in his Observations de médecine pratique (1743) he gave some indication of the clinical ideal acquired from his days at Leiden. In particular he insisted on the importance of performing autopsies in order to verify diagnoses.

L’homme machine, which marked a culminating phase in the rise of modern materialism, was not merely the work of a doctor turned philosopher; it outlined a medical philosophy in the absolute sense of the term, springing as it did from the assumption that reliable knowledge about man’s nature was forthcoming only from the facts and theories that the medical sciences—anatomy, physiology, biology, pathology—could furnish. The human being was for La Mettrie a highly complex “living machine” of unique design that only those skilled in the investigation of the body’s innermost secrets could hope eventually to explain (insofar, that is, as an explanation was possible, for the man-machine, rather than being a doctrinaire thesis, displayed heuristic and even skeptical features). Seen in historical perspective, such a position may be described as the final outcome both of the iatromechanistic tradition that had reached La Mettrie through Boerhaave and of the Cartesian automatist biology that had filtered down to him through numerious intermediaries who had already sought, in varying degrees, to extend its beastmachine concept to the study of human behavior.

The basic argument of L’homme machine was supported by different but complementary types of scientific evidence. La Mettrie cited many examples showing how particular psychological states derived from physical factors: illness, fatigue, hunger, diet, pregnancy, sexual stimulation, age, climate, and the use of drugs. Referring to data provided by comparative anatomy, he held that the great contrasts in the capabilities of the various animal species, including man himself, must be owing to the specific brain structure exhibited by each. He was astute enough to grasp, in relation to the man-machine idea, the theoretical value of the discoveries that Heller had just made concerning the irritable properties of muscle tissue. By generalizing the phenomenon of irritability, and combining it with related instances of reflex action, La Mettrie was able to picture the organism as a genuinely self-moving, inherently purposive mechanism. There were two distinguishable meanings present in this overall conception, even though its author would no doubt have regarded them as inseparable. On the primary level, the man-machine offered a strictly mechanistic interpretation of how living things are constituted and function; as such it served, in the eighteenth-century milieu, to express the counterpart of animistic or vitalistic theorizing in biology. On another and more original level, it claimed that all the mental faculties and processes in the human subject were products of the underlying bodily machine—more precisely, of its cerebral and neural components. In advancing this notion, La Mettrie was perhaps the earliest exponent of a school of psychology whose method of analysis would be consistently and rigorously physiological.

The technical documentation with which La Mettrie tried to prove his case was, to be sure, seriously limited by the knowledge then available concerning the life sciences. Even the term “machine,” as the used it, suggested no definite mechanical model that might permit one to differentiate animate from inanimate systems. In describing man as a machine, what La Mettrie really meant was, first, that man was essentially a material being structured to behave automatically; and second, that this self-sufficing organic structure, together with the psychic activities it determined—consciousness, emotion, will, memory, intelligence, moral sense—ought to be explored and clarified with the aid of the same quantitative, mechanical principles that everyone had already recognized as operative in the realm of physics. He left it to his successors to till in, as the progress of physiological psychology would allow, the concrete details of the mind-body correlation.

Several themes of interest to the history of science grew logically out of the man-machine thesis. One was the continuity it asserted between the mentality of man and that of those animals most resembling him. Supposing the observable differences in intelligent behavior among the various species to be a question merely of degree, La Mettrie ascribed these to the ascending order of complexity of be found in the central nervous apparatus of mammals from the lowliest up to man. It was his sharp awareness of the analogies between animal and human nature that led him, at one point, to entertain the experimental hope of instructing the anthropoid ape to speak. More generally, it prompted him to give a preponderant place to the instincts and other biologically conditioned needs in his evaluations of thought, felling, and conduct. In accord with such and approach to psychology, La Mettrie envisioned a broad expansion of the ordinary limits set to the usefulness of medicine. He expected that medical science—in particular what is now called psychiatry—would someday be able, by modifying for the better the all-controlling state of the organism, to effect the ethical improvement of those who required it, thereby contributing to the well-being of society. A special instance of this concern was La Mettrie’s proposal that many criminals be regarded as “sick” instead of “evil,” and that they be turned over to competent doctors for diagnosis and treatment. But it must bot be forgotten that the bond which he wished to forge between the practice of medicine and eudaemonistic or humanitarian ethics took for granted, on his part, a doctrine of physiological determinism that left no freedom to the individual, whose actions were held to be intrinsically amoral.

Among La Mettrie's other writings, the most important by far is the Histoire naturelle de l’?me, which anticipated closely, and corroborated with a richer accumulation of biological data and a greater reliance on sensationist psychology, the conclusions of L'homme machine. In that earlier treatise, however, he saw fit to set his demonstration of the materiality of the soul within the framework of a Scholastic type of metaphysics, somewhat blurring its import and leaving out of account the specifically mechanistic character of man that he was later to affirm so forcefully. The Histoire naturelle de l’?me was also, like L’homme machine, inspired in large part by an extrascientific motive. This was La Mettrie’s obvious desire, born of the free thinking an dan ticlerical tendencies of the period, to undermine religion by refuting, on the authority of biology and medicine, the dogma of the spiritual and immortal soul.

The Systéme d’Epicure (1750), an unsystematic group of reflections, gave to the naturalistic science of man sketched by La Mettrie and appropriate evolutionary dimension; more exactly, it represented the human race, no less than other animal races, as the final result of a long series of organic permutations in less perfect precursor species that had failed to survive. Although this work was among the earliest statements in the modern earl of the idea of evolution, its exposition of that idea did not go much beyond the Lucretian background on which it freely drew. In L’homme plante (1748), a minor but curious work, La Mettrie sought to confirm his belief in a sort of universal organic analogy by pointing out, at times rather speciously, what he considered to be parallel organs and corresponding vital functions in plants and in the human body.

The influence of La Mettrie on the history of science, while difficult to fix with precision, may be said generally to have promoted the objectives of the mechanistic, as against the vitalistic, school of biology and, more significantly, to have militated in favor of a science of psychology based on the physiological method of investigating the mind and personality. Moreover, his deterministic interpretation of human behavior, and his likening of it to that of animals, foreshadowed two familiar tenets of presentday behaviorist psychology. Finally, one may rank among La Mettrie’s more recent heirs those who have discovered in cybernetic technology not only the mechanical means of creating artificial thought but also a program for explaining how the brain itself thinks by assimilating its operations to the model of a computerized machine.

BIBLIOGRAPHY

I. Orginal Works. La Mettrie’s philosophical, scientific, and literary writings have never been published together in a single ed. His philosophical texts alone were published numerous times in collected form, but not since the eighteenth century. A recent photo repr. (Hildesheim, 1968) reproduces the Oeuvres philosophiques, 2 vols. (Berlin, 1774). An anthology of selected materials can be found in Marcelle Tisserand, ed., La Mettrie: Textes choisis (Paris, 1954). There are critical presentations of two individual works: Francis Rougier, L’homme plante, repub. with intro. and notes (New York, 1936); and Aram Vartanian, L’homme machchine; a Study in the Origins of an Idea, with an introductory monograph and notes (Princeton, 1960).

The only modern English trans. of La Mettrie is available in the now inadequate ed. by Gertrude C. Bussey: Man a Machine; Including Frederick the Great’s “Eulogy”, and Extracts From “The Natural History of the Soul” (Chicago—London, 1927).

II. Secondary Literature. The following are useful studies of La Mettrie’s scientific and philosophical thought: Raymond Boissier, La Mettrie, médecin, pamphlétaire et philosophe, 1709–1751 (Paris, 1931); Emile Callot, “La Mettrie,” in his La philosophie de la vie au XVIII^e sièle (Paris, 1965), ch. V, pp. 195–244; Keith Gunderson, “Descartes, La Mettrie, Language, and Machines,” in his Mentality and Machines (New York, 1971), pp. 1–38; Günther Pflug, “J. O. de Lemettrie und die biologischen Theorien des 18. Jahrhunderts,” in Deutsche Vierteljahrsschrift für Literaturwissenschaft und Geistesgeschichte, 27 (1953), 509–527;;J. E. Poritzky, Julien Offray de Lamettrie, sein Leben und seine Werke (Berlin, 1900); and GuyFrancis Tuloup, Un précurseur méconnu; Offray de La Mettrie, médecin-philosophe (Dinard, 1938).

Aram Vartanian