This extraordinary man exercised a profound influence upon those who came into contact with him. He excited almost unbounded enthusiasm and great veneration among his students. They were allowed to work close by his side, and so magnetic was his personality that he stimulated them powerfully and succeeded in transmitting to them some of his own mental qualities. As professor of physiology in Berlin, Müller trained many gifted young men, among whom were Ludwig (1816-1895), Du Bois-Reymond (1818-1896), and Helmholtz (1821-1894), who became distinguished scholars and professors in German universities. Helmholtz, speaking of Müller's influence on students, paid this tribute to the grandeur of his teacher: "Whoever comes into contact with men of the first rank has an altered scale of values in life. Such intellectual contact is the most interesting event that life can offer."
The particular service of Johannes Müller to science was to make physiology broadly comparative. So comprehensive was his grasp upon the subject that he gained for himself the title of the greatest physiologist of modern times. He brought together in his great work on the physiology of man not only all that had been previously made known, carefully sifted and digested, but a great mass of new information, which was the result of his own investigations and of those of his students. So rigorous were his scientific standards that he did not admit into this treatise anything which had been untested either by himself or by some of his assistants or students. Verworn says of this monumental work, which appeared in 1833, under the title Handbuch der Physiologie des Menschen: "This work stands to-day unsurpassed in the genuinely philosophical manner in which the material, swollen to vast proportions by innumerable special researches, was for the first time sifted and elaborated into a unitary picture of the mechanism within the living organism. In this respect the Handbuch is to-day not only unsurpassed, but unequalled."
Müller was the most accurate of observers; indeed, he is the most conspicuous example in the nineteenth century of a man who accomplished a prodigious amount of work all of which was of the highest quality. In physiology he stood on broader lines than had ever been used before. He employed every means at his command—experimenting, the observation of simple animals, the microscope, the discoveries in physics, in chemistry, and in psychology.
He also introduced into physiology the principles of psychology, and it is from the period of Johannes Müller that we are to associate recognition of the close connection between the operations of the mind and the physiology of the brain that has come to occupy such a conspicuous position at the present time.
Fig. 56.—Johannes Müller, 1801-1858.
Müller died in 1858, having reached the age of fifty-seven, but his influence was prolonged through the teachings of his students.
Physiology after Müller
