(plural of die), cubical pieces of bone or ivory, marked with dots on each of their faces, from one to six. They are used in various games of chance, by being thrown from a box.

DICÆARCHUS, a celebrated Peripatetic philosopher, historian, and geographer, was a native of Messana in Sicily. He was the contemporary of Theophrastus and Aristotle, and flourished towards the close of the fourth century B.C. The exact dates of his birth and death are unknown; the time of the latter event is approximately fixed by good authorities as the year 285 B.C. Nothing is known with certainty concerning the life of Diæearchus except that he was a disciple of Aristotle, and a friend of Theophrastus, to whom he dedicated the majority of his works. Of his writings, which comprised treatises on a great variety of subjects, none have descended to our day. Nothing but their titles and a few fragments survive. The most important of them was his *Life in Greece*, in which the moral, political, and social condition of the people was very fully discussed. Among the philosophical works of Dioclearchus may be mentioned the *Lesbiaci* in three books, in which the author endeavours to prove that the soul is mortal. This work is written in the form of a dialogue, and derived its name from the fact that the scene of the dialogue was laid at Lesbos. To it the author afterwards appended a supplement, likewise in three books, which he called *Corinthiaci*. The only complete edition of the fragments of Dioclearchus is that published at Darmstadt in 1841 by Max Fuhr. An excellent dissertation on them will be found in Osann.