Lives and Opinions of Eminent Philosophers

​Heraclides, the son of Euthyphron, of Heraclea in Pontus, was a wealthy man. At Athens he first attached himself to Speusippus; but he also attended the lectures of the Pythagoreans, was an admirer of Plato’s doctrines, and later listened to Aristotle, as Sotion says in his Successions. He wore soft garments and was of immense bulk in body, so that by the Athenians he was called not "the Pontic" (Pontikos) but "the Pompous" (Pompikos). His glance was mild and dignified. Works of his are extant that are most beautiful and excellent: dialogues, of which the ethical ones are: On Justice, three books; On Moderation, one book; On Piety, five books; On Courage, one book; On Virtue in general, one book, and another work; On Happiness, one book;

​On Rulership, one book; On Laws, one book, and works akin to these; On Names, one book; Covenants, one book; Involuntary Acts, one book; Eroticus and Cleinias, one book. The physical ones are: On the Intellect; On the Soul, and a separate work On the Soul; On Nature; On Images; Against Democritus; On Celestial Phenomena, one book; On the Things in Hades; On Lives, two books; Causes concerning Diseases, one book; On the Good, one book; Against the Doctrines of Zeno, one book; Against Metron, one book. The grammatical ones are: On the Age of Homer and Hesiod, two books; On Archilochus and Homer, two books. And also musical ones: On the Passages in Euripides and Sophocles, three books; On Music, two books;

​Homeric Solutions, two books; Theoretical Treatises, one book; On the Three Tragic Poets, one book; Characters, one book; On Poetics and the Poets, one book; On Conjecturing, one book; Perspective, one book; Expositions of Heraclitus, four books; Expositions against Democritus, one book; Eristic Solutions, two books; Axiom, one book; On Forms, one book; Solutions, one book; Admonitions, one book; To Dionysius, one book. The rhetorical works are: On Speaking Rhetorically, or Protagoras. The historical ones: On the Pythagoreans; On Inventions. Of these, some he has composed in a comic vein, such as On Pleasure and On Moderation; others in a tragic vein, such as On the Things in Hades, On Piety, and On Authority.

​He also possesses a certain middle style suitable for conversation, in which philosophers, generals, and statesmen converse with one another. There are moreover geometrical and dialectical writings of his. Above all, in all his works he is varied and elevated in diction, and capable of charming the mind effectively. He is also reputed to have freed his native city when it was under tyranny, having slain the monarch, as Demetrius of Magnesia says in his Men of the Same Name. Demetrius also relates the following tale concerning him: that he reared a serpent from its youth, and when it was fully grown, and he himself was on the point of death, he ordered one of his trusted attendants to conceal his corpse, and to place the serpent upon his bed, in order that he might seem to have passed into the company of the gods.