.C.), Greek philosopher, the third great leader
of the Stoics. A native of Soli in Cilicia (Diog. Laert. vii. 179), he
was robbed of his property and came to Athens, where he studied possibly
under Zeno, certainly under Cleanthes. It is said also that he became a
pupil of Arcesilaus and Lacydes, heads of the Middle Academy. This
impartiality in his early studies is the key of his philosophic work,
the dominant characteristic of which is comprehensiveness rather than
originality. He took the doctrines of Zeno and Cleanthes and
crystallized them into a definite system; he further defended them
against the attacks of the Academy. His polemic skill earned for him the
title of the "Column of the Portico." Diogenes Laertius says, "If the
gods use dialectic, they can use none other than that of Chrysippus";
[Greek: ei me gar en Chrysippos, ouk an en Stoa] ("Without Chrysippus,
there had been no Porch"). He excelled in logic, the theory of
knowledge, ethics and physics. His relations with Cleanthes,
contemporaneously criticized by Antipater, are considered under STOICS.
He is said to have composed seven hundred and fifty treatises,
fragments alone of which survive. Their style, we are told, was
unpolished and arid in the extreme, while the argument was lucid and
impartial.

See G.H. Hagedorn, _Moralia Chrysippea_ (1685), _Ethica Chrysippi_
(1715); J.F. Richter, _De Chrysippo Stoico fastuoso_ (1738); F.
Baguet, _De Chrysippi vita doctrina et reliquiis_ (1822); C. Petersen,
_Philosophiae Chrysippeae fundamenta_ (1827); A. Gercke, "Chrysippea"
in _Jahrbuecher fuer Philologie_, suppl. vol. xiv. (1885); R. Nicolai,
_De logicis Chrysippi libris_ (1859); Christos Aronis, [Greek:
Chrysippos grammatikos] (1885); R. Hirzel, _Untersuchungen zu Ciceros
philosophischen Schriften_, ii. (1882); L. Stein, _Die Psychologie der
Stoa_ (1886); A.B. Krische, _Forschungen auf dem Gebiete der alten
Philosophie_ (1840); J.E. Sandys, _Hist. Class. Schol._ i. 149.

CHRYSOBERYL, a yellow or green gem-stone, remarkable for its hardness,
being exceeded in this respect only by the diamond and corundum. The
name suggests that it was formerly regarded as a golden variety of
beryl; and it is notable that though differing widely from beryl it yet
bears some relationship to it inasmuch as it contains the element
beryllium. In chrysoberyl, however, the beryllium exists as an
aluminate, having the formula BeAl2O4, or BeO.Al2O3. The analy