Swiss writer, Protestant pastor, and founder of physiognomics, an antirational, religious, and literary movement.

Lavater served as pastor of St. Peter's Church in Zürich. In 1799 he was deported to Basel for a time because of his protest against the violence of the French Directory. After his return to Zürich, Lavater was wounded during a skirmish with French soldiers and later died as a result of his injuries.

Lavater's studies in physiognomy and his interest in “magnetic” trance conditions had their source in his religious beliefs, which drove him to search for demonstrable traces of the divine in human life. His belief in the interaction of mind and body led him to seek influences of the spirit upon the features.

His Physiognomische Fragmente zur Beförderung der Menschenkenntnis und Menschenliebe, 4 vol. (1775–78; Essays on Physiognomy, 1789–98), established his reputation throughout Europe. Goethe (Goethe, Johann Wolfgang von) worked with Lavater on the book, and the two enjoyed a warm friendship that was later severed by Lavater's zeal for conversion.

Lavater's most important books are Aussichten in die Ewigkeit (1768–78), Geheimes Tagebuch von einem Beobachter seiner selbst (1772–73; Secret Journal of a Self Observer, 1795), Pontius Pilatus (1782–85), and Nathanael (1786). His lyrical and epic poems are imitations of Friedrich Gottlieb Klopstock.