Porphyry's slim logic primer taught medieval scholars from Paris to Baghdad
A Phoenician philosopher born around 234 wrote a short introduction to logic that became the standard textbook for more than a thousand years, in Latin schools and across the Muslim world alike. The same man edited Plotinus, championed vegetarianism, and wrote an attack on Christianity so troubling that emperors ordered every copy burned.
His parents called him Malchus, from the Aramaic word for king, and he called Aramaic his mother tongue. Later he adopted Porphyrius, meaning clad in purple. Sources disagree over whether he was born in Tyre or in Batanaea in present-day Syria. He studied grammar and rhetoric in Athens under Cassius Longinus before the fame of Plotinus drew him to Rome in 262.
Six intense years of Neoplatonic practice, including a severely restricted diet, left him in poor mental health, and Plotinus advised him to spend five years in Sicily recovering. He returned to lecture, and after his teacher's death assembled the Enneads, the only collection of Plotinus's writings, along with a biography. Late in life he married Marcella, a philosophy student and widow with seven children.
His Isagoge sorted the ways qualities can be said of things into five headings: genus, species, difference, property and accident. Boethius's Latin version became a fixture of European schools and set up centuries of argument over universals, while the Porphyrian Tree diagram of substance still echoes in how biologists classify living things. Translated into Arabic from Syriac, it long served as the entry point to logic for Muslim students of theology, grammar and law, and many later Arabic logic books borrowed its title.
He also wrote fifteen books against the Christians while in Sicily. Around thirty apologists, Augustine and Jerome among them, answered him, and almost everything known of his arguments survives only in their rebuttals, because Theodosius II ordered the work burned in 435 and again in 448. Augustine called him the most learned of philosophers and the bitterest enemy of Christians. Like Pythagoras he argued for vegetarianism on ethical and spiritual grounds, and he disagreed openly with his successor Iamblichus over theurgy. Roughly sixty works carry his name, many fragmentary or lost, and even his death date is uncertain.
Source: Porphyry of Tyre
