GFM_2

Medieval Philosophy — Exam Study Guide

Organized, corrected, and extended from lecture notes. Citations to Marenbon, Maurer, Apolloni, and the SEP are preserved where the original notes used them.

---

Quick Timeline

Thinker	Dates	Tradition	Major Text(s)
Augustine of Hippo	354–430	Christian (Neoplatonic)	Confessions, De Trinitate, City of God, De Magistro
Boethius	c. 477–524	Christian/Neoplatonic	Consolation of Philosophy, logical commentaries
Al-Farabi	c. 872–950	Islamic Aristotelian/Platonic	On the Perfect State (Mabādiʾ)
Peter Abelard	1079–1142	Christian, nominalist	Ethics (Scito te ipsum), Historia Calamitatum
Christine de Pizan	1364 – c. 1430	Christian humanist	The Book of the City of Ladies (1405)
Thomas Aquinas	1225–1274	Christian Aristotelian	Summa Theologiae
Peter John Olivi	1248–1298	Franciscan	Summa on the Sentences, De Contractibus
Marsilius of Padua	c. 1275–1342	Christian Aristotelian/republican	Defensor Pacis (1324)
John Duns Scotus	c. 1266–1308	Franciscan, realist	Ordinatio, Lectura

Note on corrections: A few dates in the original notes appear to be typos and have been corrected above (e.g., Augustine’s dates were given as “397–480”; his actual dates are 354–430. Abelard’s death is 1142, not 1144. Marsilius’s historical trigger is the Gregorian Reform under Pope Gregory VII, not “Gregory II.”)

---

1. Augustine of Hippo (354–430)

Biography

• Often described as having three “selves”: the young pagan rhetorician, the convert wrestling with faith, and the mature Catholic bishop of Hippo.
• Wrote the Confessions (c. 397–400), generally considered the first autobiography by a Western philosopher.
• Intellectual trajectory: Manichaeism → Skepticism (New Academy) → Neo-Platonism → Christianity.
• According to John Marenbon, Augustine did not leave behind one settled system but a shifting, sometimes self-contradictory body of positions, developed dialectically over a fifty-year writing career — which is exactly why scholars distinguish an “early” from a “mature” Augustine (e.g., on free will, see below).

Key Doctrines

Free Will vs. Liberty (the “Pauline position,” per Marenbon)

• Augustine distinguishes:
  • Liberum arbitrium (free choice/the power of choice) — humans retain this even after the Fall.
  • Libertas (true liberty/freedom) — the actual capacity to will and do the good.
• After the Fall, humans keep liberum arbitrium but lose libertas: they either fail to will the good, or, willing it, cannot carry it out. This sets up the mature doctrine that fallen humanity cannot but sin (non posse non peccare) without grace — a much darker view than his earlier writings against the Manichees, which stressed human responsibility for evil.

Divine Simplicity

• In De Trinitate: no predicate of God is accidental. God is not good by participation in some external Goodness — God simply is Goodness, is Greatness, etc. This blocks any composition in God (matter/form, substance/accident) and anticipates later scholastic treatments of divine simplicity (cf. Aquinas and Boethius below).

Self-Knowledge and Knowledge of God

• “O God, who art ever the same, let me know myself and thee.” Per Armand Maurer, knowing oneself is inseparable from knowing one’s soul — interior turn (in interiore homine) as the route to God, a theme that becomes central to later Augustinian epistemology (illumination, below).

Two Cities

• In City of God, Augustine breaks with classical political theory: no earthly city can ever be the just community ancient philosophy hoped for.
• Humanity is divided by the object of its love:
  • City of God — ordered by amor Dei (love of God).
  • City of Man — ordered by amor sui (love of self).
• A genuine commonwealth (res publica) requires a community organized around the true common good, and Augustine holds that only Christians can rightly identify that good — a striking and controversial restriction on what counts as a “real” political community.

Gradualist Ontology

• A Neoplatonic hierarchy of being, but importantly modified:

God
Angels
Human beings
Animals
Plants
Inanimate things

• Per Claudia Apolloni, the crucial difference from pagan Neoplatonism is that for Plotinus the One is beyond/above Being, while for Augustine, God is the supreme Being (ipsum esse) — collapsing the Neoplatonic “beyond being” into a Being-centered metaphysics that becomes standard in Christian thought.

Text 1 — Evil, Passions, and Free Will

The Problem: What is the efficient cause of evil? (Posed against the Manichees, who held evil to be a positive substance/force opposed to good.)

Augustine’s solution: Privation theory of evil

• Evil has no efficient cause because evil has no positive reality — it is not a thing but a diminishment or privation of being/good.
• God foresees sin and makes good use of even a wicked will, weaving it into a providential order Augustine likens to “a beautiful poem of antithesis” — discordant elements that contribute to an overall harmony (an aesthetic theodicy).
• Material goods are not evil in themselves; evil consists in the will’s disordered desire toward them (concupiscentia, misdirected love).
• Logical structure: the Supreme Good (God) cannot be evil, but lesser/created goods can be deficiently willed — i.e., evil only ever exists as a corruption within a good.

On the Passions

• Passions (emotions) are not intrinsically good or bad — this is a direct break from the Stoic ideal of apatheia (imperturbability).
• A Christian is, for Augustine, a passionate human being. The moral value of a passion depends entirely on its object — e.g., fear of God is good, fear of poverty might not be.

Mature Augustine on Grace

• The later Augustine (post-Pelagian controversy) holds that fallen humans cannot avoid sinning without divine grace — the famous non posse non peccare doctrine, a hardening of his earlier emphasis on voluntary responsibility for sin.

Text 2 — Insight, Illumination, and Signs

Two conditions for knowledge:

1. What you know must be true.
2. You must know that what you know is true (reflective certainty).

Illumination doctrine

• Words are of limited use in producing genuine knowledge; what we actually attain is a sudden interior insight (“illumination”).
• Christ is the inner teacher — human teachers can only prompt the learner to “consult the inner light.” This is explicitly parallel to the Platonic doctrine of recollection in the Meno (Augustine secularizes/Christianizes anamnesis into illumination by the divine Logos).
• All knowledge ultimately derives from either sense perception or intellectual understanding — but words function only to redirect attention, not to transmit content directly. (This is the core argument of De Magistro, “On the Teacher.“)

Theory of Signs

• Definition: “A sign is a thing that of itself causes something else to enter into thought beyond the appearance it presents to the senses.”

• Taxonomy:

  • Natural signs (e.g., smoke signifying fire — no intention behind the signifying).
  • Intentional/given signs (signs deliberately produced to communicate), further divided into:
    • Naturally given signs (e.g., a cry of pain — instinctive but still expressive/intentional).
    • Conventional signs (e.g., words — arbitrary, agreed-upon).

• No direct correspondence between sign and thing — meaning is mediated.

• Triadic structure of signification:

  1. The sign (external, sensible item),
  2. Signifying (the act of meaning, performed by a mind),
  3. The significate (the thing in the world referred to).

  This triadic model anticipates later medieval (and even modern, e.g. Peircean) semiotics.

Augustine — Key Terms

Term	Meaning
Liberum arbitrium	Free choice (retained after the Fall)
Libertas	True freedom to will/do the good (lost after the Fall)
Amor Dei / Amor sui	Love of God / love of self — basis of the Two Cities
Non posse non peccare	”Not able not to sin” — mature doctrine of fallen will
Privatio boni	Privation-of-good theory of evil
Illuminatio	Divine illumination as the source of certain knowledge

Sample Exam Questions

• How does Augustine’s privation theory of evil resolve the Manichean dilemma about the cause of evil?
• Explain the distinction between liberum arbitrium and libertas. Why does this distinction matter for Augustine’s theory of grace?
• Compare Augustine’s theory of signs with his account of illumination — what role do words play if genuine knowledge comes from inner light alone?
• Why does Augustine claim only Christians can identify the true common good of a commonwealth? Is this compatible with classical (Aristotelian/Ciceronian) political theory?

---

2. Boethius (c. 477–524)

Biography

• Trained in Neoplatonic philosophy; central to medieval philosophy in three ways:
  1. Chief transmitter of ancient logic to the Latin Middle Ages (translations/commentaries on Porphyry and Aristotle’s logical works).
  2. Author of short, methodologically innovative theological treatises (opuscula sacra).
  3. Author of the Consolation of Philosophy — one of the most widely read works of the Latin Middle Ages, written while Boethius awaited execution on a charge of treason under Theodoric.
• Planned to translate all Greek philosophical literature into Latin, but completed only the logical works of Porphyry and Aristotle before his death — a fact with enormous historical consequences, since this is largely all the West had of Aristotle until 12th-century retranslation.

Philosophical Context

• Coined the term Quadrivium for the four mathematical liberal arts: Arithmetic, Geometry, Astronomy, Music.
• Adopted the post-Aristotelian tripartite division of practical philosophy: Ethics, Politics, Economics.
• Logic’s status is ambiguous in Boethius: is it a part of philosophy or merely an instrument (organon) for it? Boethius suggests the analogy of a hand, which is both an organic part of the body and a tool/instrument used by it.

On God

• God is supremely good and the source of all goods; human happiness consists in participation in God.
• Nature begins whole and perfect, later declining into “inferior productions” (a degenerative, not progressive, view of cosmic history).
• God is pure form without matter, lacking all composition, and therefore absolutely one (cf. Augustine’s divine simplicity, above).

Soul and Knowledge

• Boethius accepts Plato’s doctrine of the pre-existence of the soul and the associated doctrine of recollection (anamnesis): truth-seekers must “search within,” since Ideas are not abstracted from sense experience but are innate memories from a prior existence.
• Reason is held to be the highest power of human beings (above imagination and sense).

Text — Divine Foreknowledge and Future Contingents

The Problem: If God’s knowledge is infallible and God knows future contingent events, then those events cannot happen otherwise than foreknown — but then there is no free will. This is the problem of divine prescience.

Boethius’s three-part solution:

1. Modes of Cognition Principle

   “Everything which is known is grasped not according to its own power, but rather according to the capability of those who know it.”

   • Knowledge is shaped by the knower’s mode of cognition, not solely by the nature of the object known. A single fact can be known in different ways (contingently by us, necessarily-as-present by God) without changing the ontological status of the fact itself.

2. Eternity

   “Eternity is the whole, simultaneous, and perfect possession of unending/boundless life.”

   • God’s eternity is not endless duration through time but a timeless, total presence — God does not “foresee” in the sense of looking ahead through a temporal gap; all of time is simultaneously present to God’s single eternal “now.” (Marenbon stresses this radical difference between divine eternity and human temporal experience.)

3. Simple vs. Conditional Necessity

   “There are really two necessities: one simple, as that all men are mortal; the other conditional, as for example, if you know someone is walking, it is necessary that he is walking… this conditional necessity by no means carries with it that other, simple, kind.”

   • Simple necessity: true in all circumstances, unconditionally (e.g., “all men are mortal”).
   • Conditional necessity: true only given some further fact (e.g., “if X is walking, necessarily X is walking while he is walking” — but X was not necessitated to walk in the first place).

Putting it together: Because God is eternal, He “sees” future contingents as though present (via the Modes of Cognition Principle + Eternity). God’s knowledge therefore imposes only conditional necessity on events (“if God knows X will happen, then X will happen”) — not simple necessity. Since conditional necessity does not entail simple necessity, human free will is preserved even under infallible divine foreknowledge.

Boethius — Key Terms

Term	Meaning
Quadrivium	Arithmetic, geometry, astronomy, music
Eternity (aeternitas)	Total, simultaneous, timeless possession of life — God’s mode of existence
Simple necessity	Unconditional necessity (true in every circumstance)
Conditional necessity	Necessity true only relative to a given fact (does not entail simple necessity)

Sample Exam Questions

• Explain how Boethius’s “Modes of Cognition Principle” helps dissolve the apparent conflict between divine foreknowledge and human freedom.
• What does Boethius mean by calling God “eternal” rather than merely “everlasting”? Why does this distinction matter for the foreknowledge problem?
• Distinguish simple from conditional necessity, and explain why this distinction is the linchpin of Boethius’s solution.

---

3. Peter Abelard (1079–1142)

Biography

• A traumatic forced castration (arranged by the family of Héloïse, whom he had secretly married) was the turning point of his life; he subsequently became a monk.
• Studied under Anselm of Laon (not to be confused with Anselm of Canterbury) but was quickly forced to leave, reportedly after openly criticizing Anselm’s teaching.
• 1140: condemned at the Council of Sens; 1141: condemnation ratified by Pope Innocent II.
• Sought refuge at the monastery of Cluny under Peter the Venerable; died in 1142 (note: the original notes’ “1144” is a slip).
• Famous declaration of faith over philosophy: “I do not want to be a philosopher if it is necessary to deny Paul. I do not want to be Aristotle if it is necessary to be separated from Christ.” (echoing Acts 4:12, “there is salvation in no other name”).

Philosophical Context — Nominalism

• Abelard held a nominalist approach to logic: he was a rationalist, but did not subordinate faith to reason or treat them as wholly separate domains.
• Theory of mental images:
  • Confused/general images: represent no individual distinctly, but a whole class vaguely (evoked by common nouns, e.g. “man”).
  • Particular/detailed images: represent one individual distinctly (evoked by proper names, e.g. “Socrates”).
  • For Abelard, universal concepts are nothing but these confused mental images — there is no extra-mental universal “humanity”; only individual things exist, and the universal is a product of how the mind processes likeness among individuals (a form of conceptualism, often classed alongside, but more sophisticated than, pure nominalism).

Text — Ethics of Intention (Scito te ipsum)

Central claim:

“An action is good not because it contains within it some good, but because it issues from a good intention.” (Conversely, bad intention makes an act bad.)

• This is the natural ethical consequence of Abelard’s nominalism: since universals (and, by extension, “act-types”) have no independent reality, moral evaluation cannot rest on the act itself, but only on the individual agent’s interior state — his core concern is the individual moral agent’s personal guilt and responsibility.

Conditions on a “good” intention

• It is not enough for an intention to merely seem good; it must be really good, i.e., it must correspond to God’s intention/will.
• Ignorance exculpates acting in good faith: if someone is genuinely ignorant of God’s will and acts against it believing they act rightly, they do not sin. Example: the persecutors of Christ did not sin, because they did not know what they were doing.
• Famous distinction: It is not a sin to feel lust for another’s spouse — the sin is consenting to that lust (I.49). Desire (suggestion/temptation) ≠ sin; consent is what constitutes sin.

Willing vs. Accomplishing

• Just as willing is not the same as accomplishing the will, sinning is not the same as carrying out the sin:
  • Sinning = the mind’s consent.
  • Carrying out the sin = the external act/result.
• This radically internalizes morality: the external deed adds nothing to the moral guilt, though it may add to social/legal consequence.

Three stages of sin (illustrated by Eve and the forbidden fruit):

1. Suggestion (temptation presents itself),
2. Pleasure (the will is drawn/delighted),
3. Consent (the will assents) — this final stage alone constitutes sin proper.

Morality vs. Legal Judgment

• Abelard distinguishes the court of law from moral judgment: it can be justified for courts to impose a penalty greater than the sin itself, in order to deter others by example — “For human beings don’t judge about what is hidden but about what is plain” (I.82).
• Only God can judge intentions — human courts judge external acts because intentions are hidden from us.

Summary verdict: Abelard’s ethics is one of radical subjectivism/internalism — acts have no intrinsic moral nature; the sole criterion of moral worth is the conformity of the agent’s intention to the divine intention.

Important Concepts

• Morals: “the mind’s vices or virtues that dispose us to bad or good deeds” (I.1) — a disposition, not the act itself.
• Actions under duress (I.11–15): willing something under genuine duress should not be condemned as morally bad.

Abelard — Key Terms

Term	Meaning
Confused image	Mental representation of a class (universal), tied to common nouns
Particular image	Mental representation of an individual, tied to proper names
Consent (consensus)	The decisive moral act — the will’s assent to a desire
Scito te ipsum	”Know thyself” — Abelard’s Ethics, emphasizing self-examination of intention

Sample Exam Questions

• Explain why Abelard’s nominalism about universals leads naturally to his “ethics of intention.”
• Why, for Abelard, is lusting after another’s spouse not itself sinful, while consenting to that lust is? What does this reveal about his view of the will?
• How does Abelard reconcile the practice of harsh legal punishment with his view that intrinsic moral guilt depends solely on intention?

---

4. Al-Farabi (c. 872–950)

Biography

• A committed Aristotelian, tracing his intellectual lineage teacher-by-teacher back to Aristotle; central figure of the Baghdad Peripatetic school.
• Heavily influenced by Plato’s political philosophy (especially the Republic).
• Held that philosophy as practiced by Plato and Aristotle is the route to true human happiness (saʿāda/felicity) — reasserting the ancient (rather than purely revelation-based) path to flourishing.

Text — On the Perfect State (Mabādiʾ Ahl al-Madīna al-Fāḍila)

Foundational premise: No human being is self-sufficient; everyone needs others for the necessities of life — hence humans naturally form societies (15.1).

Three kinds of perfect society (graded by completeness):

1. Great society — the union of all societies in the inhabited world.
2. Medium society — the union of one nation.
3. Small society — the union of a single city.

• Imperfect societies (villages, city quarters, etc.) exist only for the sake of perfect societies (15.2) — they are not self-sufficient ends in themselves.
• The city is the smallest unit at which true human excellence/felicity can first be attained — felicity in the city contributes to the felicity of the nation, which contributes to the felicity of the universal (world) state.

The City as a Body (organic analogy, 15.3–15.4)

• The excellent city is like a healthy body: a natural hierarchy in which each part performs its proper function.
• The ruler’s relation to the rest of the city mirrors the First Cause’s relation to the rest of existence (15.6) — a direct cosmological-political analogy.

Conditions for Rulership (15.7)

1. An inborn natural predisposition.
2. The acquired habit/will for rulership.

Nature of the Ideal Ruler (15.8, 15.11)

• He has “reached his perfection,” having become actual intellect (fully actualized in understanding) and grasps the intelligibles.
• He is “the man who knows every action by which felicity can be reached.”

Twelve Natural Qualities Required of the Perfect Ruler (15.12):

1. Strong limbs and organs (fit for the tasks of rule)
2. Excellent natural understanding/perception
3. Excellent memory (forgets almost nothing)
4. Intelligence and quick-wittedness
5. Fine/eloquent diction
6. Fondness for learning
7. Fondness for truth
8. Lack of craving for food, drink, sex, gambling
9. Pride of spirit / love of honor
10. Indifference to worldly wealth
11. Love of justice
12. Strength of will (firmness in carrying out the good once recognized)

• Since such a person is extremely rare, Al-Farabi allows that rule can be exercised by someone with only 6 of these qualities, or 5 plus the gift of prophecy (15.12).

Six Additional Acquired Qualities (developed in maturity, 15.13):

1. Being a philosopher
2. Knowing the laws/customs of earlier rulers
3. Excelling at legal analogy (deriving new rulings from precedent)
4. Excellent deliberation about novel circumstances
5. Skilled rhetorical guidance of the people
6. Mastery of military art and physical toughness

Distribution of Rule (15.14)

• If one person has all the qualities → he is king.
• If several people together possess them collectively → they jointly rule.
• If no philosophers are involved in governance at all, the city is destined to perish — philosophy is non-negotiable for political health.

Five Types of City (overall typology):

1. The Excellent City — knows and pursues true felicity.
2. The Ignorant City — its people do not know true felicity (subdivided below).
3. The Wicked City — shares the excellent city’s correct views but acts like the people of the ignorant city (a kind of hypocrisy/akrasia at the civic level).
4. The City which deliberately changed its character — formerly matched the excellent city in both view and action, but has since corrupted itself.
5. The City which missed the right path through faulty judgment — aims at felicity, but its first ruler falsely claimed to receive revelation.

Six Subtypes of the Ignorant City (15.15–20) — each organized around a false conception of the human good:

1. City of Necessity — pursuit of bare survival needs.
2. City of Meanness — pursuit of wealth/riches.
3. City of Depravity/Baseness — pursuit of sensual pleasure.
4. City of Honor — pursuit of honor and fame.
5. City of Power — pursuit of domination.
6. Democratic (Free) City — pursuit of freedom as such, without higher orientation.

Class psychology: “The souls of people of one class are like one soul” — whether ruling or subordinate, members of a class share a collective psychological character (16.1).

Eight Things the People of the Excellent City Must Know:

1. The First Cause and its qualities.
2. Immaterial beings (their qualities and ranks).
3. The celestial substances and their qualities.
4. Natural bodies beneath the celestial spheres.
5. The generation of humans and the faculties of the soul.
6. The first ruler and how revelation occurs.
7. Successive rulers after the first.
8. That the people of the excellent city attain felicity, while others attain wretchedness.

Pluralism note: Al-Farabi allows that excellent nations/cities can differ in religion while still being excellent (17.1–2) — felicity is the common goal; revealed religion is, in a sense, an image/symbol of philosophical truth suited to a particular people.

• Ignorant and erring cities can arise even from religions that were originally correct, through later corruption by their adherents (18.1).

Al-Farabi — Key Terms

Term	Meaning
Felicity (saʿāda)	True human flourishing, the highest good
Perfect society	Self-sufficient society — city, nation, or world-state
Wicked City	Correct beliefs, corrupt practice
Ignorant City	Wrong beliefs about the good (6 subtypes)

Sample Exam Questions

• Why does Al-Farabi think philosophical knowledge (not merely good character) is a precondition for legitimate rulership?
• Compare the “Wicked City” and the “Ignorant City” — what is the philosophical significance of separating belief from practice in his typology?
• How does Al-Farabi’s organic (body) analogy for the city function philosophically? Compare with Marsilius’s use of a similar analogy (see §8).

---

5. Christine de Pizan (1364 – c. 1430)

Context

• Author of The Book of the City of Ladies (1405). Often read as the first work of systematic European feminist philosophy, written partly in response to misogynist works like Jean de Meun’s continuation of the Roman de la Rose.

The Central Question

Why have so many men — including reputable philosophers and respected writers — been so ready to say and write abominable, hateful things about women’s nature?

• The difficulty is sharpened by the fact that these critics are not cranks but esteemed authorities, which makes their misogyny seem more authoritative/credible than it should be.

Method

• De Pizan is visited by three allegorical figures — Reason, Rectitude, and Justice — who help her construct, point by point, a symbolic “City of Ladies” as a refutation of misogynist tradition and a record of women’s virtue and achievement.

Why Do Men Slander Women? (Reason’s Answer)

Reason denies that misogyny is rooted in nature — instead, it stems from varied human motives:

1. Misguided good intentions — generalizing from the faults of a few women to condemn women as a whole (overgeneralization).
2. Depravity/projection — men who were sexually frivolous in youth turn on women once old age makes them impotent (a kind of bitter scapegoating).
3. Envy — straightforward resentment of women’s qualities or success.

Reinterpreting Misogynist Commonplaces

• A Latin proverb claimed God made women “to weep, talk, and weave” — intended as an insult (implying women are merely weak, talkative, and domestic).
• Reason reverses the valence: these are in fact virtues properly understood — e.g., tears can move hearts toward good: the example given is Augustine’s mother (Monica), whose weeping and persistent prayer were instrumental in Augustine’s own conversion to Christianity — turning a supposed weakness into spiritually consequential strength.

Practical and Theological Conclusions

• The text closes with advice to women on conduct: be humble and patient, but also firmly defend one’s own honor and chastity when threatened.
• This advice is explicitly addressed to women of every social rank — aristocratic, bourgeois, and lower-class alike (de Pizan is unusually explicit about class inclusivity for her time).
• Core theological claim: woman cannot be an inherently vile/base creature, since she too was created in the image of God (imago Dei) — a direct theological rebuttal of misogynist essentialism.

Sample Exam Questions

• How does de Pizan use the allegorical figures of Reason, Rectitude, and Justice structurally and rhetorically?
• Explain how de Pizan’s reinterpretation of “weep, talk, weave” exemplifies her broader argumentative strategy against misogynist commonplaces.
• In what ways does de Pizan’s argument anchor itself in orthodox Christian theology (rather than rejecting it) to defend women?

---

6. Thomas Aquinas (1225–1274)

Biography

• Studied under Albert the Great (Albertus Magnus).
• Dominican friar; Regent Master at the University of Paris.
• Some of his positions were implicated in the broader Condemnations of 1277 (a set of Parisian propositions targeting “radical Aristotelianism,” not exclusively Aquinas); he was canonized in 1323.

The Five Ways (Summa Theologiae I, q.2, a.3)

Aquinas’s proofs are not original arguments invented from scratch — each has roots in ancient or earlier medieval philosophy — but Aquinas redirects them toward the Christian God specifically, rather than the more impersonal “Prime Mover” of Aristotle or the philosophers’ God of Avicenna/Averroes.

The First Way — Argument from Motion (detailed in the notes):

• Premise: Things are observably in motion.
• Premise: Whatever is moved must be moved by another (a mover distinct from the moved, in the relevant respect).
• Key metaphysical concepts:
  • Potency: the capacity to become something not yet actual.
  • Act: actuality already achieved.
  • Motion = the reduction of potency to act.
• A thing cannot bring itself from potency to act; it requires something already in act. (Example: wood, potentially hot, is made actually hot only by something actually hot, e.g. fire.)
• Apparent counterexample — self-movers (living things): On closer analysis, self-movers are not exceptions: they have parts, one of which moves another (e.g., the soul/appetite moves the limbs) — so the “self-mover” is still, internally, a case of one thing being moved by another.
• If the mover is itself moved, it requires a further mover, and so on. An infinite regress of movers is impossible — without a first, unmoved mover, there would be no subsequent movers at all, hence no motion. Therefore: a First Unmoved Mover exists → God.

The Other Four Ways (extension, for completeness):
2. From Efficient Causation — nothing causes itself; an infinite regress of causes is impossible; there must be a First (Uncaused) Cause.
3. From Contingency (the “argument from necessity”) — contingent beings (which could fail to exist) cannot account for their own existence indefinitely; there must be a Necessary Being that grounds all contingent existence.
4. From Gradation of Perfection — things are more or less good, true, noble, etc.; such grading implies a maximum standard by which all else is measured → God as the supreme standard of perfection.
5. From the Governance of the World (teleological/design argument) — natural things act toward ends/order even without intelligence of their own; this requires an intelligent designer directing them toward their ends.

Goodness, Being, and Evil

• “Goodness precedes being only in the way the final cause precedes the efficient cause.” (I.e., goodness and being are convertible/co-extensive — every being, insofar as it is a being, is good — but conceptually goodness is approached through final causality, being through efficient causality.)
• Evil is not a positive entity but a privation/lack of due existence/perfection — directly continuing Augustine’s privation theory (§1 above).
• Illustration: an eye can be “bad” through privation of sight (blindness), because sight is proper to the eye; but a leg cannot be “bad” through lack of sight, because sight is not owed to a leg in the first place. Evil = the lack of a good that is properly due to a thing’s nature.

God as Pure Actuality

• God is actus purus — pure act, with no unrealized potency whatsoever. This underwrites divine simplicity, immutability, and necessity (cf. Augustine, Boethius above).

Comparative Note — Bonaventure vs. Scotus on Matter and Act

• Bonaventure (standard 13th-century Aristotelian assumption): even angels cannot be wholly immaterial; they must be compounds of form and “spiritual matter,” because matter = potentiality and form = actuality — and only God can be pure actuality without any admixture of potency. (So any creature, even an angel, must have some matter to supply its potency.)
• Scotus later denies the unqualified equation of matter with potentiality and form with actuality — opening conceptual space for wholly immaterial creatures (pure forms) that are still not God, because they remain composite in other ways (e.g., via the form/individuating-haecceity distinction — see §9).

Aquinas — Key Terms

Term	Meaning
Potency / Act	Capacity-to-be vs. actuality
Actus purus	”Pure act” — God, with no unrealized potential
Privatio	Privation — Aquinas’s (Augustinian) account of evil
Five Ways	Aquinas’s five arguments for God’s existence

Sample Exam Questions

• Reconstruct the First Way in full logical steps. Why does Aquinas think an infinite regress of movers is impossible?
• Why can a blind eye be called “bad” but not a blind leg? What does this tell us about Aquinas’s general theory of evil as privation?
• Contrast Bonaventure’s and Scotus’s views on whether angels require “spiritual matter.” What is at stake metaphysically in this disagreement?

---

7. Peter John Olivi (1248–1298)

Biography

• Franciscan friar, educated in Paris; deeply suspicious of pagan philosophy, believing its authors were fundamentally misled about the nature of reality.
• Enjoyed little institutional prestige and was at times forbidden to teach.
• Anticipated several ideas later developed more famously by Duns Scotus.

Philosophical Context

The Will and Human Distinctiveness

• Olivi holds that almost everything distinguishing humans from animals depends on free will — anticipating the strong “voluntarist” current of 14th-century thought (which culminates in Scotus and Ockham’s emphasis on will over intellect).

Rejection of Aristotelian Categories as Ontologically Basic

• Olivi was among the first to deny that Aristotle’s categories track real ontological divisions. We cannot infer the structure of reality directly from our conceptual/predicative divisions:

  “The diversity of modes of predication does not necessarily entail a diversity of modes of being, because the mode of predication follows the mode of understanding rather than the mode of being.”

• I.e., the way we talk or think about something (predication) reflects our mode of understanding, not necessarily an independent ontological fact about the thing itself.

Rationes Reales vs. Rationes Secundum Dici

• Olivi is broadly nominalist but with realist intuitions — a middle position:
  • Rationes reales (“real aspects/respects”): the mind can consider one and the same reality under different aspects (e.g., considering Socrates in terms of his height and his weight) without thereby committing to the independent existence of “quantity” as a distinct thing. Yet these aspects are not purely mind-dependent either — they are genuine properties of reality, just not ontologically distinct entities.
  • Rationes secundum dici (“aspects according to how something is said”): these are wholly mind-dependent — products purely of how we describe/predicate, with no corresponding real foundation.

Universal Hylomorphism (with a twist)

• Olivi accepts universal hylomorphism: every substance except God is a composite of form and matter.
• But, following Bonaventure, he divides matter into radically distinct kinds: corporeal matter and spiritual matter (the latter explaining the composite nature of supposedly “immaterial” beings like angels and souls — see the Bonaventure/Scotus contrast in §6 above).

Against Concurrentism

• Concurrentism = the view that God directly participates as a causal partner in every created causal process (nothing happens without God’s active causal contribution at every instant).
• Olivi rejects this, because accepting it would mean God is implicated as a co-cause of human sin whenever a human sins — an unacceptable theological consequence. Denying concurrentism preserves human beings as the sole responsible causes of their own sinful acts.

Mental Words

• Olivi holds that our interior “mental words” are always accompanied by an act of thought and are shaped by that thought. He believes these mental words, properly understood, give us better access to and understanding of the external world.

Text — Language and Social Objects

Question posed: Does the right of royal authority over a kingdom (or property right over one’s home) add anything real beyond the persons and things of which it is predicated?

Olivi’s answer: No — such rights/social relations add no further reality beyond the underlying persons and things. (This is a striking proto-nominalist/deflationary analysis of social and legal entities — rights and authority are not extra “things” added to the world, but ways of describing relations among existing persons/objects, consistent with his rationes secundum dici framework above.)

Olivi — Key Terms

Term	Meaning
Rationes reales	Real (but not ontologically distinct) aspects of a thing the mind can consider separately
Rationes secundum dici	Purely mind-dependent ways of describing a thing
Concurrentism	View that God co-causes every created causal act (Olivi rejects this)
Spiritual matter	The “matter” component Olivi (following Bonaventure) attributes to immaterial substances like souls/angels

Sample Exam Questions

• Explain Olivi’s distinction between rationes reales and rationes secundum dici. Why is this distinction necessary for someone trying to combine nominalist and realist intuitions?
• Why does Olivi reject concurrentism? What theological problem is he trying to avoid?
• What does Olivi’s analysis of royal/property rights as “adding nothing real” suggest about his broader metaphysics of social relations?

---

8. Marsilius of Padua (c. 1275–1342)

Biography

• 14th-century philosopher, Paris Arts Master; author of Defensor Pacis (“Defender of Peace,” 1324), an attack on papal claims to secular jurisdiction.
• Historical background: the Gregorian Reform, initiated by Pope Gregory VII in the 11th century (the Investiture Controversy), generated escalating tension between popes and secular rulers that lasted for centuries.
• The Defensor Pacis was dedicated to Ludwig (Louis) of Bavaria, the Holy Roman Emperor then at war with the papacy — the work functions almost as Ludwig’s political manifesto.
• After publication, Marsilius fled Paris for Ludwig’s court, which also hosted William of Ockham, Francis of Marchia, and John of Jandun.

Text — On Civil Society

Opening Polemic: Peace vs. Discord

• Discord is “the diseased disposition” of the civil regime; a city/state cannot achieve its primary goal without peace.
• Marsilius’s central target throughout is the papalist position (papal “plenitude of power”) — i.e., the claim that the pope has total jurisdiction over secular rulers and indeed over every human being.

Natural Sociability

• Man is naturally social, organizing into communities to secure common utility, quoting Cicero (Tully), echoing the Stoics: “the things that grow in the world are all created for the use of man, but men are born for the sake of men.”

Four Meanings of “State”

1. A number of cities/provinces under one regime.
2. A particular species of regime (e.g., a temperate monarchy).
3. A combination of (1) and (2).
4. Something common to every temperate monarchy (an abstraction across regimes).

Tranquility

• Defined as the good disposition of the city/state whereby each of its parts can perform its proper function in accordance with reason and its own establishment.
• Marsilius compares the relation of city-to-tranquility with the relation of an animal to health — health is the proper functioning of all the animal’s parts together; tranquility is the analogous political “health.”

Origin of the Civil Community (Ch. 3)

• Following Aristotle, communities develop from less perfect to more perfect forms.
• Marsilius adopts Aristotle’s definition of the city: “the perfect community, having the full limit of self-sufficiency, which came into existence for the sake of living, but exists for the sake of living well.”
• He distinguishes “living” from “living well,” and further distinguishes each into a heavenly/eternal and an earthly kind. Marsilius claims philosophers (working by natural demonstration alone) have only ever grasped the earthly kind — the heavenly kind belongs to revealed theology, beyond philosophy’s reach. Earthly living and living well are achievable only within a civil community.
• Men first organized communities to secure sufficiency, but then needed moral teachers/judges to resolve disputes and quarrels.

Six Offices/Classes of the City
To meet the differing needs that sufficiency demands, the city divides into six functional classes, grouped into two tiers:

Tier	Classes	Function
Honorable	Priestly	Maintains order by instilling fear of wrongdoing; priests must be righteous, respected men — farmers/artisans should not serve as priests
	Warrior	Protects the city from enslavement (living well is impossible for an enslaved citizenry)
	Judicial	”Mends the excesses” of acts so they accord with correct proportion — i.e., adjudicates disputes
Vulgar	Agricultural	Produces food
	Artisanal	Produces crafted goods
	Financial	Manages treasure/resources across plentiful and scarce years

The Four Causes of the City and Its Parts

• Material cause: men habituated by diverse arts/disciplines.
• Efficient cause: the minds and wills of men, through individual or collective thoughts/desires.
• Formal cause: commands — i.e., the efficient cause as it is “impressed upon” the person carrying out a determinate civic function.
• (Final cause differs between the city as a whole and its individual parts — the city’s overall final cause is the common good/living well; each part’s final cause is its specific function within that whole.)

Six Forms of Government (three “good”/tempered, three corrupt — directly modeled on Aristotle’s Politics):

Good (ruled with consent, for common benefit)	Corrupt (ruled without consent, for private benefit)
Kingly Monarchy — one ruler, common benefit, with subjects’ consent	Tyranny — one ruler, private benefit, without consent
Aristocracy — an honorable class rules, common benefit, with consent	Oligarchy — a group rules for its own benefit, without consent
Polity — every citizen participates per his rank/ability, common benefit, with consent	Democracy (in Marsilius’s pejorative Aristotelian sense) — the “vulgar” class rules alone, without consent, not for the common benefit

(Note: Marsilius’s “democracy” here follows Aristotle’s technical, negative usage — rule by the common people for their own narrow benefit — and should not be confused with modern positive usages of the term.)

Five Methods of Establishing a Kingly Monarchy

1. The monarch is appointed to one determinate function in ruling the community (e.g., Agamemnon as leader of the Achaean league).
2. Hereditary succession.
3. Election of the king.
4. The first ruler is elected, with subsequent hereditary succession.
5. The ruler holds authority over everything in the community.

Voluntary vs. Involuntary Government

• Every government governs either voluntary or involuntary subjects: voluntary government is the genus of well-tempered (good) regimes; involuntary government is the genus of diseased (corrupt) regimes.
• This is why Marsilius favors electing the king — and the best men should rule via polity generally.

Popular Legislative Authority

• Good government also requires good laws, and laws should be made by the very people to whom they will apply — i.e., by the whole body of citizens or its weightier/major part.
• Best law = that made for the common benefit of all citizens (citing Aristotle’s Politics).
• Marsilius gives both a theoretical and a practical argument for popular legislation:
  • Theoretical: “Since all citizens must be measured by the law according to due proportion, and no one knowingly harms or wishes injustice to himself, it follows that all or most wish a law conducive to the common benefit.” I.e., self-interest aligned with collective authorship tends to produce just law.
  • Practical: even an objectively less useful law will be better obeyed if people themselves made it, because people respect what they have authored — a point about political psychology/legitimacy independent of the law’s intrinsic quality.

Reply to the “Common People Are Unwise” Objection

• Objection: most people lack the technical skill to draft good laws.
• Marsilius’s reply: even without the skill to produce something well, people often can judge its quality — proven by induction: many people can judge the quality of a painting, a house, a ship, etc., without being able to make one themselves. So the people’s incapacity to draft law does not entail incapacity to recognize bad law or to consent wisely to good law.

Marsilius — Key Terms

Term	Meaning
Defensor Pacis	Marsilius’s main work; “Defender of Peace”
Tranquility	The civic analogue of bodily health — proper functioning of all parts
Plenitude of power	The papalist claim Marsilius attacks — total papal jurisdiction over secular affairs
Polity	Rule by citizens generally, per rank/ability, for the common good, with consent

Sample Exam Questions

• Why does Marsilius think law must be made by the citizens themselves, rather than merely for their benefit by an enlightened few?
• Reconstruct Marsilius’s “induction” argument against the objection that ordinary people are unfit to legislate.
• Compare Marsilius’s six-fold class structure of the city with Al-Farabi’s account of the perfect city (§4). What role does “honor” play in each?
• How does Marsilius’s distinction between voluntary and involuntary government map onto his six forms of government?

---

9. John Duns Scotus (c. 1266–1308)

Biography

• One of the most influential High Medieval philosophers; nicknamed “the Subtle Doctor” (Doctor Subtilis) for the intricacy of his thought.
• Generally ranked second in philosophical importance only to Aquinas.
• A Franciscan friar.

Philosophical Context

Accidental vs. Substantial Change

• Accidental change: the subject retains numerical identity through the change (e.g., a person going from pale to tan — still the same individual).
• Substantial change: the underlying substance itself does not persist (e.g., death, or combustion — one substance ceases and another begins).

Plurality of Substantial Forms

• Scotus denies universal hylomorphism in the strict sense and argues that some substances possess more than one substantial form simultaneously (e.g., a human being may have both a “corporeal form” giving the body its organization and a rational soul as a further substantial form) — a controversial departure from the strict Thomistic “one substantial form per substance” rule.

Text — Realism about Universals: The Problem of “Horseness”

The Problem (from Avicenna/Ibn Sina):

• How can “horseness” (the common nature shared by all horses) be neither numerically one nor numerically diverse?
• If horseness were numerically one, then one single thing would somehow be present, whole and entire, in many different individual horses simultaneously — which seems absurd.
• If horseness were numerically diverse (i.e., a different “horseness” in each horse, with nothing literally shared), then there would be nothing genuinely common explaining why two horses are both horses, rather than merely similar.

Scotus’s Solution: “Less-than-Numerical Unity” (the Common Nature)

• Scotus introduces a third category between numerical unity and mere diversity: the common nature (natura communis) has a real unity that is less than numerical unity — it is genuinely one in some respect, without being one individual the way Socrates is one individual.

Scotus’s Supporting Arguments (two given in the notes, of his seven total):

1. The abstraction argument: If every real unity were numerical unity, then every real diversity would likewise be numerical diversity — meaning all distinct things would be equally distinct from one another. But this is false: the intellect can abstract something genuinely common from Socrates and Plato (namely, humanity) that it cannot abstract from Socrates and a mere geometrical line. This graded “commonality” requires a unity weaker than strict numerical identity but stronger than nothing at all.
2. The “opposite of black” argument: Consider the opposite of a black thing — it must be a real, white thing (since everything real has some unity, by the principle that every real thing is “one”). Yet this white thing is not numerically one in the relevant sense, since any white thing at all stands as the “opposite” of that black thing — meaning the relevant unity (whiteness as such, opposed to blackness) is common across many particular white things, not tied to one numerically singular individual.

The Individuation Solution: Haecceity

• The common nature (e.g., “humanity”) is indifferent to existing in any number of individuals — in itself it does not demand to belong to exactly one thing.
• But the common nature never exists in extra-mental reality on its own — it only exists “contracted” to a particular individual by that individual’s haecceity (haecceitas — literally “thisness”), a unique, non-qualitative principle of individuation.
• Example: the common nature humanity exists fully in both Socrates and Plato, but in Socrates it is individuated/“contracted” by Socrates’s haecceity, and in Plato by Plato’s haecceity. (SEP)

Significance: Scotus’s position is a moderate/sophisticated realism — universals are genuinely real (mind-independent), but they never exist “loose,” unindividuated, in the world; individuation is supplied by a further metaphysical principle (haecceity) distinct from the common nature itself, and distinct from mere matter (cf. his rejection of the strict matter = potency / form = act equation, contra Bonaventure, §6 above).

Scotus — Key Terms

Term	Meaning
Common nature (natura communis)	The genuinely real but “less-than-numerically-one” universal shared by individuals of a kind
Haecceity (haecceitas)	The unique, non-qualitative “thisness” that individuates a common nature into a particular
Less-than-numerical unity	Scotus’s proposed third category of unity, between strict numerical oneness and mere diversity

Sample Exam Questions

• Explain Avicenna’s “horseness” puzzle. Why do both horns of the dilemma (numerically one / numerically diverse) seem unacceptable?
• What work does “haecceity” do in Scotus’s metaphysics that the common nature alone cannot do?
• How does Scotus’s rejection of “matter = potency, form = act” (contra Bonaventure) connect to his theory of individuation?
• Compare Scotus’s realism about universals with Abelard’s nominalism (§3) and Olivi’s middle position (§7). Where does each draw the line between mind and reality?

---

Cross-Cutting Themes for Synthesis Questions

A. The Problem of Universals — A Spectrum

Position	Thinker	View
Nominalism/Conceptualism	Abelard	Universals are mental images (confused images); no extra-mental common entity
Moderate “real but not distinct”	Olivi	Rationes reales — real aspects, not ontologically separate entities
Moderate Realism	Scotus	Common natures are really (mind-independently) one in a “less-than-numerical” way; individuated by haecceity
(Implicit realism, theological)	Augustine, Aquinas	Universals ultimately grounded in divine ideas/exemplars

B. Free Will and Determinism

• Augustine: liberum arbitrium survives the Fall, but libertas (capacity to do good) is lost without grace — tension between voluntarism and the “cannot but sin” doctrine.
• Boethius: defends compatibility of divine foreknowledge with human freedom via eternity + conditional necessity.
• Abelard: locates moral freedom/responsibility entirely in the inner act of consent.
• Olivi: makes free will the very mark of human distinctiveness from animals; rejects concurrentism to preserve full human responsibility for sin.

C. The Nature of Evil

• Augustine: evil = privation of being/good; no efficient cause; aesthetic theodicy (“poem of antithesis”).
• Aquinas: evil = privation of a due perfection (the blind-eye/blind-leg distinction) — directly inherits and refines Augustine’s account.

D. Divine Simplicity and the Nature of God

• Augustine: no accidental predication of God — God is his attributes.
• Boethius: God is pure form without matter, absolutely one; eternity as timeless total presence.
• Aquinas: God as actus purus, pure actuality with no potency.

E. Political Philosophy — Three Models of the “Perfect” Community

Thinker	Basis of legitimate community	Who can recognize the common good
Augustine	Shared object of love (amor Dei)	Only Christians
Al-Farabi	Philosophical knowledge of true felicity	Only the philosopher-ruler (or those with prophecy)
Marsilius	Popular consent and self-legislation	The citizen body as a whole

F. Matter, Form, Act, and Potency — A Running Debate

• Bonaventure: matter = potency, form = act, always — hence even angels need “spiritual matter.”
• Scotus: denies this strict equation — allows wholly immaterial created substances; individuation handled instead by haecceity.
• Olivi: keeps universal hylomorphism (matter+form in everything but God) but divides matter into corporeal/spiritual kinds — a position between Bonaventure’s and Scotus’s.

---

Master Glossary

Term	Thinker(s)	Definition
Amor Dei / Amor sui	Augustine	Love of God vs. love of self; basis of the Two Cities
Actus purus	Aquinas	Pure actuality; God has no unrealized potency
Concurrentism	Olivi (rejects)	View that God co-causes every creaturely act
Conditional vs. simple necessity	Boethius	Necessity relative to a condition vs. unconditional necessity
Consent	Abelard	The decisive inner act constituting sin
Eternity	Boethius	Timeless, total, simultaneous possession of life — God’s mode of being
Haecceity	Scotus	The non-qualitative “thisness” individuating a common nature
Illumination	Augustine	Direct, sudden insight from the inner divine teacher (Christ)
Liberum arbitrium / Libertas	Augustine	Free choice (retained) vs. true freedom-to-do-good (lost at the Fall)
Natura communis	Scotus	The common nature — really one in a “less-than-numerical” way
Privatio boni	Augustine, Aquinas	Evil as a privation/lack of due good, not a positive entity
Quadrivium	Boethius	Arithmetic, geometry, astronomy, music
Rationes reales / secundum dici	Olivi	Real-but-not-distinct aspects vs. purely mind-dependent aspects
Res publica	Augustine	A genuine commonwealth, ordered to the true common good

---

Suggested Essay/Synthesis Prompts

1. Trace the concept of evil as privation from Augustine to Aquinas. What problems does this theory solve, and does it fully succeed?
2. Compare the solutions Boethius and Augustine each offer to reconcile divine power/knowledge with human freedom. Are their strategies compatible with one another?
3. “Universals are nothing but mental images” (Abelard) vs. “Universals are really, if less-than-numerically, one” (Scotus). Reconstruct both positions and assess which better handles the problem of how Socrates and Plato can both genuinely be human.
4. Compare three medieval visions of the ideal political community — Augustine’s City of God, Al-Farabi’s Excellent City, and Marsilius’s self-legislating polity. What grounds legitimate authority in each, and who is capable of perceiving the common good?
5. How does Peter Abelard’s nominalism shape his “ethics of intention”? Could a realist about universals consistently hold the same ethical theory?
6. Discuss Christine de Pizan’s use of orthodox Christian theology (creation in God’s image, exempla like Augustine’s mother) to construct an explicitly pro-woman argument. How does this strategy compare to her contemporaries’ more secular or purely polemical defenses of women?
7. Olivi rejects concurrentism and Aristotelian-categories-as-ontology; Scotus rejects strict matter=potency/form=act. What common methodological commitment, if any, unites these two Franciscan departures from the Thomistic mainstream?

---

End of study guide.