He studied at
Göttingen, where he took the degree of a doctor of medicine, and established his reputation by the dissertation,
De irritabilitate (1751). After traveling in the
Netherlands and
France, he practised as a
city physician () in Brugg, and wrote
Über die Einsamkeit ("
Of solitude", 1756, 1784–1785) and
Vom Nationalstolz ("
Of national pride", 1758). These books made a great impression in
Germany, and were translated into almost every European language. In Zimmermann's character there was a strange combination of sentimentalism, melancholy and enthusiasm; and it was by the free and eccentric expression of these qualities that he excited the interest of his contemporaries. Another of his books, written at
Brugg,
Von der Erfahrung in der Arzneiwissenschaft ("
Of experience in pharmacology", 1764), also attracted much attention. In 1768 he settled at
Hanover as a private physician of
George III with the title of a Hofrat.
Catherine II invited him to the court of
St Petersburg, but this invitation he declined. He attended
Frederick the Great during that monarch's last illness, and afterwards issued various books about him, of which the chief were
Über Friederich den Grossen und meine Unterredung mit ihm kurz vor seinem Tode (
"On Frederick the Great and my conversation with him shortly before his death", 1788) and
Fragmente über Friedrich den Grossen (
"Fragments on Frederick the Great", 1790). According to the
Encyclopædia Britannica Eleventh Edition, "[t]hese writings display extraordinary personal vanity, and convey a wholly false impression of Frederick's character." He has a daughter named
Katharina von Zimmermann who died in her 20s from
tuberculosis, which also killed her mother and grandmother. == Works ==