Isaeus

Isaeus (Greek: Ἰσαῖος Isaios; fl. early 4th century BC) was one of the ten Attic Orators according to the Alexandrian canon. He was a student of Isocrates in Athens, and later taught Demosthenes while working as a metic speechwriter for others. Only eleven of his speeches survive, with fragments of a twelfth. They are mostly concerned with inheritance, with one on civil rights. Dionysius of Halicarnassus compared his style to Lysias, although Isaeus was more given to employing sophistry.

The time of his birth and death is unknown, but all accounts agree in the statement that he flourished (ἤκμασε) during the period between the Peloponnesian War and the accession of Philip II of Macedon, so that he lived between 420 and 348 BC. He was a son of Diagoras, and was born at Chalcis in Euboea; some sources say he was born in Athens, probably only because he came there at an early age and spent the greater part of his life there.

He was instructed in oratory by Lysias and Isocrates. He was afterwards engaged in writing judicial orations for others, and established a rhetorical school at Athens, in which Demosthenes is said to have been his pupil. The Suda states that Isaeus instructed him free of charge, whereas Plutarch relates that he received 10,000 drachmas; and it is further said that Isaeus composed for Demosthenes the speeches against his guardians, or at least assisted him in the composition. All particulars about his life are unknown, and were so even in the time of Dionysius, since Hermippus, who had written an account of the disciples of Isocrates, did not mention Isaeus at all.

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