Medieval Philosophy

Period: ~200–1400 A.D. | Context: fusion of Greek philosophy with Christian, Islamic, and Hebrew theology; transition from cosmocentrism to theocentrism/anthropocentrism

General Overview

Medieval philosophy structures itself around theological-philosophical problems: the relationship between faith and reason, the existence of God, creation ex nihilo, immortality of the soul, universals. The period is divided into:

1. Patristic period (centuries I–VIII): Church Fathers interpret Christianity using Greek philosophical tools
2. Scholasticism (centuries VIII–XIV): systematic rationalization of theology in medieval schools and universities

Part I — Patristic Period

Philo of Alexandria (~20 B.C.–50 A.D.)

• First Hellenistic Jewish philosopher: fusion of the Old Testament with Platonism; profoundly influenced the Church Fathers
• Method: allegory (allegorical interpretation of the Bible)
• Logos: second God / mind of God / mediator between God and the world (anticipates Christology)

Apostolic Fathers (1st–2nd centuries)

Clement of Rome, Ignatius of Antioch, Polycarp of Smyrna — disciples of the apostles; concern with moral and ascetic matters.

Apologist Fathers (2nd century)

Defend Christianity before paganism using philosophical arguments:

• Justin Martyr: first Christian Platonist; takes up Philo’s doctrine of the Logos; humans possess “seeds of the Logos”
• Clement of Alexandria: harmony between faith and reason; philosophy as preparation for the Gospel
• Origen (~185–254): knowledge of God exceeds the human mind; incarnation of the soul for purification; influence of Middle Platonism and Ammonius Saccas (teacher of Plotinus)

Latin Patristic Period — Before Augustine (centuries III–IV)

• Tertullian (~160–225): “It is certain, because it is impossible” (De Carne Christi V) — faith and reason are irreconcilable; faith is superior
• Ambrose of Milan (~340–397): uses Philo’s allegorical method; teacher of Augustine
• Jerome (~347–420): Latin translation of the Bible — the Vulgate

Saint Augustine of Hippo (354–430)

The greatest philosopher of the Patristic period and one of the most influential in the entire history of thought.

Intellectual Biography

Path through: Cicero → Manichaeism (Persian dualism: good/evil) → Academic Skepticism → Neoplatonism (Plotinus) → Christianity (baptized by Ambrose, 387)

Fundamental Theses

i. Faith and Reason “Believe so that you may understand, understand so that you may believe” — Believe to comprehend; comprehend to believe. Faith and reason are reconcilable and mutually imply each other.

ii. Illumination There is no Platonic reminiscence; knowledge comes from God who illuminates our reason from within — a divine spark in the soul.

iii. Proofs of God’s Existence

• From truth: truth exists (even the skeptic admits this by doubting); God is the source of truth
• Degrees of perfection: there are degrees of goodness → there is a supreme good = God
• Consensus gentium: all peoples believe in something divine

iv. Trinity Substantial identity of the three persons; vestiges of the Trinity in the mind: being/knowing/loving

v. Creation ex nihilo It is not generation (as father/son) nor fabrication (as craftsman); God creates from nothing, together with time.

vi. Seminal Reasons God creates the world with “seeds” of all possible things — potentialities that develop over time (anticipates evolution?)

vii. Time Emerges with creation. Three presences in the soul: memory (past), intuition/attention (present), expectation/anticipation (future)

viii. Evil

• Metaphysical: evil does not exist; there are only degrees of perfection
• Moral: evil is the fruit of a bad will that turns toward inferior goods
• Physical: consequence of original sin

ix. Will and Grace Free will exists (sin is voluntary choice); but divine grace is necessary for the good. Original sin corrupted freedom.

x. The Two Cities

• Earthly City (Cain): founded on love of self to the point of contempt for God
• City of God (Abel): founded on love of God to the point of contempt for self
• Linear history with eschatological end

Works

Part II — Scholasticism

Structure of the Period

• 1st phase (end of 5th century – end of 9th century): Boethius, John Scotus Eriugena
• 2nd phase (end of 9th century – end of 12th century): Anselm, Abelard, dispute of universals
• 3rd phase / Golden Age (13th century): Thomas Aquinas, Bonaventure, Arabic/Hebrew philosophy
• 4th phase (14th century): crisis, Duns Scotus, Ockham

1st Phase

Boethius (~480–524)

• Translates and comments on Aristotle’s Logic into Latin — transmission to the Middle Ages
• The Consolation of Philosophy (written in prison): philosophy teaches true happiness = drawing near to God, withdrawal from material goods; trusts in Providence despite evil
• References: The Consolation of Philosophy, Commentary on Porphyry’s Isagoge

John Scotus Eriugena (~815–877)

• Reader of Neoplatonism and Pseudo-Dionysius
• 4 divisions of reality: 1) that creates and is not created (God); 2) that creates and is created (Logos/archetypes); 3) does not create and is created (world); 4) does not create and is not created (God as end)
• There is no difference between philosophy and religion
• Periphyseon (On the Division of Nature)

2nd Phase — The Dispute of Universals

The problem: Do universals (humanity, goodness, circle) exist in reality or are they merely names?

Anselm of Canterbury (1033–1109)

• “I believe so that I may understand” — believe to understand
• Ontological Argument (a priori): God = “that than which nothing greater can be thought”; if he existed only in the mind, he would not be the greatest conceivable → God exists in reality
• A posteriori proofs: degrees of goodness, greatness, causes, perfection
• Critics: Gaunilo, Thomas, Kant; defenders: Duns Scotus, Descartes, Leibniz
• Works: Monologion, Proslogion, Why God Became Man

Abelard (~1079–1142)

• “Understand in order to believe” — reason must examine before accepting on faith
• Conceptualism: universals are abstract concepts formed by the mind
• Morality of Intention: the act is neutral; good/evil resides in the intention of conscience
• Sic et Non: dialectical method applied to theology (bringing contradictory authorities into confrontation)
• Works: Sic et Non, Ethics or Know Thyself

3rd Phase — Golden Age (13th century)

Arabic Philosophy

Avicenna / Ibn Sīnā (980–1037)

• Fundamental distinction between being (what exists in fact) and essence (what a thing is)
• God: necessary being by itself; creatures: contingent/possible being
• Theory of Intelligences: God emanates 10 intelligences that govern the heavens; the 10th radiates forms onto the world and actualizes the human intellect
• Works: The Book of Healing (Shifa), The Book of Salvation

Averroes / Ibn Rushd (1126–1198)

• “The Commentator” — defending that Aristotle is the supreme philosophical truth
• Unique Intellect: there is one possible intellect for all humanity; the individual intellect is not immortal
• Eternity of the world: derived from the eternity of the Unmoved Mover (final cause, not efficient)
• Influence: Latin Averroism (Siger of Brabant); dispute over faith and reason
• Works: Commentaries on Aristotle; The Destruction of the Destruction

Hebrew Philosophy

Maimonides (1138–1204)

• Combines Aristotle with Judaism
• Negative theology: we can only say what God is not
• Creation in time (against Averroes’s eternity of the world): preserves divine freedom
• Works: Guide for the Perplexed

Major Scholastics

Albert the Great (~1200–1280)

• Introduces Aristotle to the Christian West; teacher of Thomas Aquinas
• Philosophy and theology have different perspectives but can coexist

Thomas Aquinas (1225–1274)

The greatest synthesizer of Scholasticism; harmonizes Aristotle with Christianity.

i. Ontology

• Distinction: essence (what a thing is) and act of being/existence (what exists in fact)
• Only in God does essence = existence; God is pure act
• Creatures: “have” existence (contingent), they are not existence
• Transcendentals of being: one, true, good

ii. The Five Ways (proofs of God’s existence)

1. Motion: everything that moves is moved by another → Unmoved Mover = God
2. Efficient cause: series of causes → Uncaused Cause = God
3. Contingency: contingent beings presuppose necessary being = God
4. Degrees of perfection: graduated perfections require maximum perfection = God
5. Finality: beings without intelligence act with purpose → Ordering Intelligence = God

iii. Theory of Law

• Eternal law: rational plan of God for the universe
• Natural law: human rational participation in eternal law (“do good, avoid evil”)
• Human law: derived from natural law by deduction (ius gentium) or specification (ius civile)
• Divine law: revealed law (Gospel)

iv. Politics

• Best government: monarchy (unity and order); worst: tyranny

Works: Summa Theologiae, Summa Against the Gentiles, On Being and Essence, Commentaries on Aristotle

Bonaventure (1221–1274)

• Franciscan; Platonic-Augustinian
• God is present in every cognitive act; it is not necessary to prove his existence from without
• Creation by seminal reasons and exemplarism (God uses the Ideas of his mind as project)
• The creature is a vestige (vestigium) of God
• Works: The Mind’s Journey into God (Itinerarium Mentis in Deum), Commentaries on the Sentences

Siger of Brabant (~1240–1282)

• Latin Averroism: the philosophy of Aristotle, followed consistently, leads to conclusions contrary to faith
• Doctrine of Double Truth (attributed by adversaries): reason and faith move in different directions; for the Christian it is fitting to choose faith, but the philosophical reasons have their own validity

Roger Bacon (~1214–1292) — Oxford

• Causes of ignorance: authoritarianism, presumption, habit, lack of wisdom — anticipates Bacon (17th century)
• Defends the experimental method (scientia experimentalis)

4th Phase — Crisis (14th century)

Duns Scotus (~1266–1308)

• Univocity of Being: the simplest and most universal concept is “being” — predicable of God and creatures in the same sense (against Thomas, who defended analogy)
• Formal Distinction: real (Socrates ≠ Plato) / formal (intelligence ≠ will within the same being) / modal / of reason
• Haecceity (haecceitas): principle of individuation — “this-ness” that makes a being this concrete individual
• Voluntarism: primacy of will over intellect, in God and in man
• Works: Ordinatio, Oxford Commentary, Treatise on the First Principle

William of Ockham (~1287–1347)

• Prince of Nominalists
• Ockham’s Razor: “do not multiply beings without necessity” — reduce universals, eliminate superfluous entities from metaphysics
• Universals = logical terms, not external realities; knowledge is always of singulars
• Radical Autonomy of Faith and Reason: truths of faith are not evident nor demonstrable by reason
• The Church as a free community of believers, not absolute papal government — anticipates the Reformation
• Works: Summa of Logic, Questions on the Sentences

General References

• Giovanni Reale & Dario Antiseri, History of Philosophy, vol. 2 (Patristic and Scholastic)
• Etienne Gilson, Philosophy in the Middle Ages
• Frederick Copleston, History of Philosophy, vols. 2 and 3
• Boethius: The Consolation of Philosophy (Port. trans. WMF/Martins Fontes)
• Thomas Aquinas: Summa Theologiae (ed. Loyola); On Being and Essence
• Augustine: Confessions; The City of God (ed. Paulus/WMF)