Vesalius

views updated May 14 2018

Vesalius Andreas Vesalius (1514–64) was the Renaissance physician who truly put anatomy on the medical map. In his pathbreaking De humani corporis fabrica (On the fabric of the human body, 1543), he boldly presented himself as the first to expose the errors of his predecessors: ‘How much has been attributed to Galen, easily leader of the professors of dissection, by those physicians and anatomists who have followed him, and often against reason!’

Born Andreas van Wesele, in Brussels, where his father was pharmacist to the Emperor Charles V, Vesalius learned Latin and Greek and enrolled in the Paris Faculty of Medicine, studying under the conservative humanist Sylvius, then Galen's great champion — in later years Sylvius became a scourge of Vesalius, wittily calling him vesanus (madman). Vesalius learnt his dissecting skills from Guinther von Andernach, and when in 1536 war forced him to flee Paris, he returned to Louvain, where he introduced dissection; he showed his anatomical zeal by robbing a wayside gibbet, smuggling the bones back home and there reconstructing the skeleton.

In 1537 he moved to Padua, where he made his anatomical name. Dissection had previously been demonstrated there by surgeons, and had never been mandatory for physicians. The rediscovery of Galen's On Anatomical Procedures, and the wider dissemination of his On the Use of Parts, however, meant that humanists were beating the drum for the subject, and the appointment of the young physician was one consequence of this. Vesalius's Tabulae anatomicae sex (Six anatomical pictures, 1538) were amongst the first anatomical illustrations specifically designed for students. The first three sheets were drawn by Vesalius himself and represented the liver and its blood vessels, together with the male and female reproductive organs, the venous system, and the arterial system. He was still viewing the body through Galenic eyes: despite Berengario, he drew the rete mirabile; the liver was still five-lobed, and the heart an ape's.

Thereafter Vesalius grew more critical. Familiarity with human anatomy as well as Galen's anatomical writings drove him to the unsettling conclusion that the master had dissected only animals, and forced him to see that animal anatomy was no substitute for human. He now began to challenge him on points of detail: for instance, that the lower jaw comprised a single bone, not two, as Galen, relying on animals, had stated. Evidently, human anatomy must be learned from dead bodies, not dead languages.

In 1539 he acquired a larger supply of cadavers of executed criminals and worked on his great masterpiece, the De humani corporis fabrica. Finishing it in 1542, he took it to Basel, where the press of Joannes Oporinus published it in 1543 as one of the pearls of Renaissance printing. It presents exact descriptions of the skeleton and muscles, the nervous system, the blood vessels, and the viscera. Though it contains no shattering discoveries, it marks a watershed in the medical understanding of bodily structures, for Vesalius interrogated Galen by reference to the human corpse. Others had criticized odds and ends of Galenic anatomy, but Vesalius was the first to review it systematically. The Fabrica gained immensely from the contribution of the artist, Jan Stephan van Calcar, also from the Netherlands, who provided the text with technically accurate drawings displaying the dissected body in graceful, life-like poses. The work also enunciated clear methodological principles: the anatomist–lecturer must perform the dissection himself, the eye was preferable to authority, and anatomy was the skeleton key to medicine.

Book I of the Fabrica began in Galenic fashion with the bones rather than, as in medieval practice, the internal organs. Various Galenic lapses were corrected — for instance, that the human sternum has not seven but three segments. Book II dealt with the muscles, and included the famous suite of illustrations showing ‘muscle-men’ at different stages of corporeal ‘undress’. Book III, on the vascular system, was less accurate because Vesalius still based his descriptions partly on animal material. Book IV described the nervous system, following the Galenic classification of the cranial nerves into seven pairs. Book V dealt with the abdominal and reproductive organs, where he corrected Galen's belief in the five-lobed human liver (a shape characteristic of lower animals). He nevertheless still accepted the Galenic physiological tenet that the liver produced blood from chyle, while denying that the vena cava originated in the liver — an observation that, had Vesalius been more physiologically-minded, might have begun the erosion of the Galenic belief in two distinct vascular systems, the venous, originating in the liver, and the arterial, stemming from the heart.

Book VI was devoted to the thorax. Examining the heart, Vesalius cast doubt on the permeability of the intraventricular septum: ‘we are driven to wonder at the handiwork of the Almighty by means of which the blood sweats from the right into the left ventricle through passages which escape the human vision.’ In the second edition (1555), that implicit denial of the septum's permeability was made direct. Here lay a milestone of Renaissance anatomy, for it encouraged anatomists like Realdo Colombo to conceive of the pulmonary transit, which was later used by William Harvey as evidence of the circulation of the blood. Another crucial correction of Galen came in Book VII, on the brain, where Vesalius denied the existence of the rete mirabile in humans.

In the end, Vesalius's importance lay in daring to think the unthinkable: that Galen might actually be wrong, and Galen-worship with it. The Fabrica thus laid the groundwork for a new, observation-based anatomy, announcing a new principle of fact-finding and truth-testing in anatomy: all anatomical statements were to be subjected to the test of human cadavers.

The frontispiece of the Fabrica presents the dreams, the programme, the agenda, of the new medicine. The cadaver is the central figure. Its abdomen has been opened so that everyone can peer in; it is as if death itself had been put on display. A faceless skeleton points toward the open abdomen. Then there is Vesalius, who looks out at us as if he were extending an invitation to anatomy. Medicine would thenceforth be about looking inside bodies for the truth of disease. The violation of the body would be the revelation of its truth.

Roy Porter

Bibliography

O'Malley, C. D. (1964). Andreas Vesalius of Brussels 1514–1564. University of California Press, California.


See also Galen; Harvey.

Vesalian

views updated May 17 2018

Vesalian of or pertaining to Andreas Vesalius (1514–64), Flemish anatomist, the founder of modern anatomy. His major work, De Humani Corporis Fabrica (1543), contained accurate descriptions of human anatomy, but owed much of its great historical impact to the woodcuts of his dissections.