Latin Averroism

Quick Facts

• Name: Latin Averroism
• Other names: radical Aristotelianism, heterodox Aristotelianism
• Main period: 13th-14th centuries, with later afterlives in Renaissance Italy
• Main setting: the arts faculties of medieval universities, especially Paris
• Main sources: Aristotle, read through Ibn Rushd, known in Latin as Averroes
• Famous disputes: the unity of the intellect, the eternity of the world, the authority of philosophy, and the "double truth" accusation
• Main critics: Thomas Aquinas, other theologians, and church authorities behind the Paris condemnations of 1270 and 1277

The Big Question

How far can a philosopher follow Aristotle's arguments when they seem to clash with Christian teaching?

Latin Averroists thought philosophy had its own rules. A natural philosopher should reason from the principles of natural philosophy. A theologian should reason from revelation. Trouble began when those methods seemed to point in different directions: toward an eternal world, one shared human intellect, and a high status for philosophy on one side; toward creation in time, individual souls, resurrection, and the priority of faith on the other.

In One Minute

Latin Averroism was not an organized sect. It was a cluster of 13th-century university positions associated with arts masters who read Aristotle through Ibn Rushd's commentaries and treated that reading as serious philosophical science.

The most famous issue was the unity of the intellect. Averroes argued that the highest receptive intellect is one and shared by all human beings. Aquinas attacked this view because it made "this person understands" hard to explain and seemed to threaten personal immortality.

The other famous issue was the eternity of the world. Aristotle's physics looked as if motion, time, and the cosmos had no first moment. Christian teaching said the world was created by God and had a beginning. Opponents accused the Averroists of "double truth," meaning one truth for philosophy and another for faith. That charge is famous, but it is better read as a hostile description of their strong separation between philosophical demonstration and theological belief.

Main Ideas

• Commentary: a close explanation of an authoritative text. Medieval commentaries were not passive summaries. They defined problems, settled meanings, and built new arguments. Averroes was called "the Commentator" because his Aristotle commentaries became a major guide for Latin readers.
• Demonstration: strict proof from the proper principles of a science. "Science" here means organized knowledge of causes, not modern lab work. Physics, metaphysics, ethics, and grammar each had their own starting points.
• Unity of intellect: the claim that the highest intellect used in universal thinking is one for all humans. It does not mean everyone has the same memories. It means universal understanding depends on a shared intellectual power.
• Eternity of the world: the claim that motion, time, and the cosmos have no first moment under Aristotelian natural philosophy.
• Autonomy of philosophy: the claim that philosophy may reach conclusions by its own method, without borrowing theological premises to make the answer safer.

How It Works

Latin Averroism grew inside scholasticism, especially the university arts faculty. Arts masters taught logic, natural philosophy, psychology, metaphysics, and ethics. They were expected to teach Aristotle, and Averroes's commentaries supplied a powerful way to read him.

The typical move was to ask what follows "according to the philosopher" or "according to natural reason." Suppose a natural philosopher studies motion. Aristotle's principles say every motion comes from a prior motion. If that is the rule of physics, then a first motion looks impossible inside physics. A Christian may still believe in creation, but that belief comes from faith, not from a physical proof.

This method created tension. Boethius of Dacia's answer was close to this: the natural philosopher must speak as a natural philosopher, while the believer accepts that God can do what natural philosophy cannot explain.

Church authorities saw the danger. In 1270, the bishop of Paris, Etienne Tempier, condemned propositions connected with intellect, necessity, and eternity. In 1277, he issued a larger condemnation of 219 propositions. The text did not name Siger of Brabant or Boethius of Dacia, but later scholarship has treated them as major targets of the crackdown on radical Aristotelianism.

Aquinas accepted Aristotle as a great philosopher, but rejected the Averroist reading of intellect. He argued that each human being has an individual intellectual soul, so Socrates himself understands, chooses, learns, and survives death.

Key Ideas With Examples

• Possible intellect: the receptive power that receives universal meanings. "Possible" means able to understand before actually understanding. If you can learn geometry, your intellect is possible with respect to geometry before the lesson begins.
• Agent intellect: the active power that makes universal meanings intelligible. The usual example is light: colors can be seen only when light makes them visible.
• Unity of intellect: the claim that the possible intellect is one for all human beings. Example: my memory of a triangle and your memory of a triangle are private images, but the universal truth "a triangle has three sides" is not private in the same way.
• "This person thinks": Aquinas's objection. If there is only one intellect, why say this student understands the proof rather than a shared intellect understanding through the student?
• Eternity of the world: the claim that the world has no first moment in time. If every motion requires a prior motion, natural philosophy seems unable to arrive at a first motion.
• Double truth: the accusation that philosophy and faith can state opposite truths. Modern historians often treat this as a hostile label, not a simple confession by the masters themselves.
• Radical Aristotelianism: following Aristotle's method even when the result sounds theologically unsafe. "Radical" here means unusually strict or provocative in applying Aristotelian principles.

Key People

• Ibn Rushd: the Arabic philosopher whose commentaries gave Latin readers their main Averroist sourcebook.
• Aristotle: the ancient philosopher whose works on soul, nature, motion, metaphysics, and demonstration structured the debate.
• Siger of Brabant: a Paris arts master often treated as the leading 13th-century Latin Averroist, especially on intellect and eternity.
• Boethius of Dacia: a Paris arts master who defended the autonomy of the sciences.
• Thomas Aquinas: the most important opponent of the Averroist intellect doctrine. He argued that Aristotle himself supported individual human understanding.
• Etienne Tempier: bishop of Paris who issued the condemnations of 1270 and 1277 against propositions seen as dangerous to Christian teaching.
• John of Jandun: a later medieval Averroist who shows that Averroist Aristotelianism continued beyond the first Paris crisis.

Important Works

• Long Commentary on Aristotle's De Anima, Ibn Rushd: the central source for the debate over soul, agent intellect, possible intellect, and the unity of intellect.
• Aristotle, De Anima: the base text on soul and intellect, especially how thought grasps universal forms rather than private images.
• Aristotle, Physics and On the Heavens: sources for arguments about motion, time, the heavens, and whether the world has a beginning.
• Siger of Brabant, Questions on the Third Book of Aristotle's De Anima: a Paris text on whether Aristotle and Averroes require one shared intellect for the human species.
• Boethius of Dacia, On the Eternity of the World: argues that natural philosophy cannot prove a temporal beginning of the world from its own principles.
• Boethius of Dacia, On the Supreme Good: presents the philosophical life as the highest human life available by reason.
• Thomas Aquinas, On the Unity of the Intellect Against the Averroists: the classic attack on the shared-intellect thesis.

Why It Matters

Latin Averroism matters because it made the university ask how much independence philosophy really has. Can a teacher state the best philosophical conclusion even when theology rejects it?

It also matters for the history of mind. If universal truth is shared, what belongs to the individual thinker: memory, images, attention, soul? Aquinas's reply helped define the later Christian Aristotelian view that each person has an individual intellectual soul.

The controversy also shows how powerful Arabic philosophy was in Latin Europe. Averroes was a Muslim philosopher writing in Arabic, but his commentaries became major teaching tools in Christian universities.

Proponents, Critics, and Opponents

The main proponents were arts masters and later university Aristotelians who thought Averroes gave the best reading of Aristotle. Siger of Brabant and Boethius of Dacia are the central 13th-century names, though historians debate how neatly the label "Averroist" fits them.

The main critics were theologians who thought these views damaged Christian doctrine. Aquinas attacked the unity of intellect because it seemed to remove individual understanding and personal immortality. Other opponents worried about determinism, denial of creation in time, and overpraise of the philosopher's life.

The institutional opponents were church authorities, especially at Paris. Tempier's condemnations tried to mark limits around what could be taught.

Related Pages

• Ibn Rushd
• Aristotle
• Thomas Aquinas
• Scholasticism
• Aristotelianism
• Long Commentary on Aristotle's De Anima