First of all, the _medical systems and theories of the century_. Many hundred years previously Galen had originated a method, which deserves, perhaps, the title of pure eclecticism. The first purely eclectic system similar to his originated with Boerhaave (1688-1738), perhaps the most famous physician of his or any other century. He was the son of a clergyman near Leyden, Holland, and was one of thirteen children. Originally intended for the clerical profession, he had studied philosophy, history, logic, metaphysics, philology, mathematics, as well as theology, with great diligence. His education was, later, directed to the study of medicine, because of the statement that the purity of certain theological doctrines was endangered by him. So he studied chemistry and botany, and then anatomy and medicine,{194} graduating in 1693. He practiced in Leyden with great success, and was offered a court position. In 1709 he was tendered the chair of Medicine and Botany, and in 1714 that of the Practice of Medicine; in 1718 he was also made Professor of Chemistry. In all of these positions he displayed the greatest capacity. He was a clinical teacher of rare talent, and soon acquired such reputation as to attract to Leyden students from all parts of the world in such numbers that no lecture-room in the university could contain them. He was the first to give separate lectures on the subject of ophthalmology, and employed the magnifying-glass in examining the eye. As a practitioner he was no less popular, and he left an estate valued at two million dollars. He was so famous that, when a Chinese official addressed a letter "To the Most Famous Physician in Europe," it reached him safely. He made no distinction in his patients, and compelled Peter the Great to wait a whole night for his turn to consult him. His most eminent pupils were: Haller, Van Swieten, de Haën. Gaub, and Cullen. Boerhaave's influence and dignity, which were astonishing, even in a physician, were based no less upon his encyclopaedic attainments than upon the benevolence and purity of his character. He was free from disputatiousness and vanity, although everywhere regarded as an oracle. His universal maxim was: "Simplicity is the seal of truth," although he never manifested this in his therapeutics. He employed the thermometer in the axilla in examining his cases, as did the iatrophysicists of the previous century.