Aristotelianism

Where Plato's Academy pursued philosophy chiefly through dialogue and argument aimed at abstract Forms, Aristotle's Lyceum pursued it through what would now be called empirical research, collecting, comparing and classifying the natural world before drawing general conclusions from the evidence. Aristotle and his students gathered specimens and reports covering hundreds of animal species, dissected what they could, and compiled comparative accounts of governments across dozens of Greek city states, work that survives today only in the single case of Athens. This method rested on Aristotle's own logic, the system of the syllogism he developed in his logical treatises, which set out formal rules for valid reasoning that remained the standard teaching of logic in Europe until the nineteenth century.

He also divided knowledge itself into a lasting scheme of theoretical sciences aimed at truth for its own sake, practical sciences aimed at right action, and productive sciences aimed at making useful or beautiful things, a classification that shaped how universities organized their faculties for centuries afterward.

Much of what survives under Aristotle's name are not polished books meant for publication but lecture notes, dense and unevenly finished, edited and arranged by later scholars including Andronicus of Rhodes roughly three centuries after Aristotle's death, which is part of why the prose is often difficult and the argument is often compressed.

Aristotle's own school, the Lyceum, declined after his death, but his texts had a second and much longer life that had almost nothing to do with Athens. Most of his logical and scientific works passed out of general circulation in the Latin West for centuries, while in the Islamic world they were translated into Arabic beginning in the eighth and ninth centuries and became the working foundation of falsafa. Al-Kindi, Al-Farabi, Avicenna and later Averroes wrote extensive commentaries that did not merely preserve Aristotle but extended him, arguing through his logic and his account of the soul and the intellect to conclusions Aristotle himself never reached, and Averroes in particular became known in the Latin West simply as The Commentator.

That Arabic Aristotle, along with a wave of direct translation from the Greek, reached Western Europe in the twelfth century, chiefly through Toledo, and the arrival was disruptive rather than welcome. Aristotle's works on natural philosophy were formally banned from teaching at the University of Paris in 1210 and again in 1231 for conclusions that appeared to threaten the world's createdness and the soul's individual immortality. The ban did not hold. Within a generation Aristotle was the backbone of the arts curriculum at Paris and Oxford, and the project of reconciling his philosophy with Christian doctrine, carried out most influentially by Thomas Aquinas, became Scholasticism's central task and Thomism's defining one. A philosopher whose own school had quietly closed became, by way of Baghdad and Toledo, the single most assigned author in medieval Europe.

Sources Aristotle in the West: The Origins of Latin AristotelianismFernand Van Steenberghen, translated by Leonard Johnston with Avicenna (Stanford Encyclopedia of Philosophy entry)Dimitri Gutas, Averroes (Stanford Encyclopedia of Philosophy entry)Fouad Ben Ahmed and Robert Pasnau