=121.= After the death of Panaetius the school at Athens appears to have been conducted by DARDANUS and MNESARCHUS, both of Athens, jointly[54]; later we find at its head DIONYSIUS of Cyrene, who enjoyed a great reputation as a mathematician, and was a vigorous opponent of Demetrius the Epicurean[55]. About the same time[56] ATHENODORUS the elder of Tarsus (circ. 130-60 B.C.) became librarian at Pergamus; he made use of his position to erase from Zeno’s works those passages (probably from the _Republic_) which were repugnant to the Stoic teaching of his own time; he was however detected and the passages in question were restored[57]. It appears also that he counselled withdrawal from the vexations of public life, a policy by no means consistent with the teaching of Zeno, and for which he is rebuked by Seneca[58]. From him we first hear the practical precept which both Seneca and Juvenal echo, to ask nothing of the gods that you cannot ask openly[59]. In his old age he left Pergamus and came to reside at Rome with M. Porcius Cato in B.C. 70. Amongst the younger friends of Cato were ANTIPATER of Tyre, who wrote on practical ethics, and died at Athens about 45 B.C.[60]; and APOLLONIDES, with whom he conversed on the subject of suicide shortly before his death[61]. From DIODOTUS Cicero received instruction in Stoicism before 88 B.C.[62]; he conceived a great affection for him, and invited him to live in his house[63]: he remained there till his death in 59 B.C., when he left Cicero a considerable property[64]. In his old age he was blind, but he continued his studies, and in particular that of mathematics, as ardently as ever[65]. APOLLONIUS of Tyre wrote a biography of Zeno, from which Diogenes Laertius often quotes[66]. To this period perhaps belongs HIEROCLES, who was bitterly opposed to Epicurus on account of his choosing pleasure as the end of life, and still more for his denial of providence[67]. [Sidenote: Cicero.]