Work · Hellenistic, Roman & Late Antique
Isagoge (Introduction)
A short introduction to Aristotle’s Categories on genus, species, difference, property and accident – it opens by asking whether genera and species really exist, and declines to answer.
Introduction
A short Greek treatise, probably written in Sicily after 268, that introduces five terms needed for Aristotle’s Categories: genus, species, difference, property and accident. Its opening sentences list three questions Porphyry chose not to answer – whether genera and species exist or are only in the mind, whether they are bodies or incorporeal, and whether they exist apart from sensible things or in them. Boethius translated the work into Latin and commented on it twice, and the medieval dispute over universals grew out of these questions. Translated into Syriac and into Arabic by Abu Uthman al-Dimashqi, it opened the study of logic in the Islamic world as well; the diagram of genera and species later called the “Porphyrian tree” was drawn by later commentators, not by Porphyry himself.
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- Organonc. 350 BCE · Aristotle
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