His most important works, all of which were written in French, are: _Lettre sur la sculpture_ (1769), in which occurs the well-known definition of the Beautiful as "that which gives us the greatest number of ideas in the shortest space of time"; its continuation, _Lettre sur les désirs_ (1770); _Lettre sur l'homme et ses rapports_ (1772), in which the "moral organ" and the theory of knowledge are discussed; _Sopyle_ (1778), a dialogue on the relation between the soul and the body, and also an attack on materialism; _Aristée_ (1779), the "theodicy" of Hemsterhuis, discussing the existence of God and his relation to man; _Simon_ (1787), on the four faculties of the soul, which are the will, the imagination, the moral principle (which is both passive and active); _Alexis_ (1787), an attempt to prove that there are three golden ages, the last being the life beyond the grave; _Lettre sur l'athéisme_ (1787).
The best collected edition of his works is by P. S. Meijboom (1846-1850); see also S. A. Gronemann, _F. Hemsterhuis, de Nederlandische Wijsgeer_ (Utrecht, 1867); E. Grucker, _François Hemsterhuis, sa vie et ses oeuvres_ (Paris, 1866); E. Meyer, _Der Philosoph Franz Hemsterhuis_ (Breslau, 1893), with bibliographical notice.
HEMSTERHUIS, TIBERIUS (1685-1766), Dutch philologist and critic, was born on the 9th of January 1685 at Groningen in Holland. His father, a learned physician, gave him so good an early education that, when he entered the university of his native town in his fifteenth year, he speedily proved himself to be the best student of mathematics. After a year or two at Groningen, he was attracted to the university of Leiden by the fame of Perizonius; and while there he was entrusted with the duty of arranging the manuscripts in the library. Though he accepted an appointment as professor of mathematics and philosophy at Amsterdam in his twentieth year, he had already directed his attention to the study of the ancient languages. In 1706 he completed the edition of Pollux's _Onomasticon_ begun by Lederlin; but the praise he received from his countrymen was more than counterbalanced by two letters of criticism from Bentley, which mortified him so keenly that for two months he refused to open a Greek book. In 1717 Hemsterhuis was appointed professor of Greek at Franeker, but he did not enter on his duties there till 1720. In 1738 he became professor of national history also. Two years afterwards he was called to teach the same subjects at Leiden, where he died on the 7th of April 1766. Hemsterhuis was the founder of a laborious and useful Dutch school of criticism, which had famous disciples in Valckenaer, Lennep and Ruhnken.