PhilosopherMedieval philosophyLate Scholasticism

William of Ockham

Guillelmus de Ockham
Also known as: Gulielmus de Ockham, Guillelmus Occamus, William Ockham, Venerabilis Inceptor
Scholasticism

William of Ockham (c. 1287–c. 1347) was an English Franciscan friar, theologian, and logician whose razor-sharp criticism of metaphysical excess reshaped medieval philosophy. Educated within the Franciscan tradition, probably at Oxford, he absorbed and then challenged the realist metaphysics of thinkers like Thomas Aquinas and Duns Scotus. Ockham is best known for the methodological maxim later dubbed “Ockham’s razor”: do not multiply entities beyond necessity. In his hands, this became a powerful tool for trimming universal natures, abstract entities, and speculative constructs from philosophy, yielding a robust form of nominalism in which only individual substances and their qualities truly exist. Summoned to Avignon on charges of heresy, Ockham became embroiled in the conflicts of the Avignon Papacy. After fleeing to the protection of Emperor Louis IV of Bavaria, he devoted himself to political and ecclesiological writings defending Franciscan poverty and attacking papal absolutism. His contributions to logic and philosophy of language advanced the theory of supposition and mental language, while his skeptical-leaning epistemology emphasized intuitive and abstractive cognition. Ockham’s work helped loosen the hold of high scholastic metaphysics and prepared the ground for late medieval nominalism, early modern empiricism, and emerging ideas of limited government and church–state separation.

At a Glance

Quick Facts
Born
c. 1287(approx.)Ockham, Surrey, Kingdom of England
Died
c. 1347(approx.)Munich, Duchy of Bavaria, Holy Roman Empire
Cause: Probably plague or related epidemic disease
Floruit
c. 1317–1347
Period of main intellectual and political activity as theologian, logician, and critic of papal power
Active In
Kingdom of England, Papal States, Holy Roman Empire
Interests
LogicMetaphysicsPhilosophy of languageEpistemologyTheologyPolitical philosophy
Central Thesis

William of Ockham advances a rigorously parsimonious, theologically grounded nominalism in which only individual entities and their directly grounded qualities exist, universal terms are merely mental or linguistic signs, knowledge rests primarily on intuitive cognition of individuals, and both metaphysical and political authority must be constrained by what can be justified through evident reason and Scripture rather than by proliferating abstract entities or unchecked claims of power.

Major Works
Commentary on the Sentences (Ordinatio and Reportatio)extant

Ordinatio et Reportatio in quattuor libros Sententiarum

Composed: c. 1317–1322

Sum of Logicextant

Summa Logicae

Composed: c. 1323–1326

Quodlibetal Questionsextant

Quodlibeta septem

Composed: c. 1322–1324

On the Power of the Popeextant

Dialogus de potestate papae (often simply "Dialogus")

Composed: c. 1332–1342

Eight Questions on the Power of the Popeextant

Octo quaestiones de potestate papae

Composed: c. 1339–1342

On the Power of the Emperor and Popeextant

De imperatoris et pontificis potestate

Composed: c. 1338–1340

On Evangelical Poverty / On the Poverty of Christextant

Opus nonaginta dierum (along with related tractates on poverty)

Composed: c. 1332–1334

Expositions of Aristotle’s Logic (Porphyry, Categories, On Interpretation)extant

Expositio in librum Porphyrii, Expositio in Praedicamenta, Expositio in librum Perihermenias

Composed: c. 1318–1323

Key Quotes
Nothing ought to be posited without a reason, unless it is self-evident or known by experience or established by the authority of Sacred Scripture.
William of Ockham, Ordinatio I, dist. 30, q. 1

Programmatic statement of his methodological principle of parsimony, later associated with Ockham’s razor, linking ontological economy to epistemic justification and scriptural authority.

Plurality is not to be posited without necessity.
Paraphrase of Ockham’s principle; cf. Summa Logicae I, c. 12 and related passages

Canonical formulation of the razor attributed to Ockham, expressing his view that we should not multiply entities, explanations, or principles beyond what is required to save the phenomena.

A universal is not something outside the soul existing in individual things, nor something existing in the soul as a quality; rather, it is only a mental term signifying many things.
William of Ockham, Ordinatio I, dist. 2, q. 8

Concise statement of his nominalist account of universals as signs within mental language rather than as real shared natures or abstract objects.

God cannot be proved to exist by any evident proposition of reason, yet His existence is most certain through faith.
William of Ockham, Ordinatio I, dist. 2, q. 3

Illustrates his epistemic modesty and separation of what can be strictly demonstrated by natural reason from what is held on the authority of revelation.

The pope can err, even in matters of faith and morals, when he does not adhere to the rule of Scripture and the teaching of Christ.
William of Ockham, Dialogus, Part III, Tract I

Expression of his critical stance toward papal infallibility and plenitude of power, grounding ecclesial authority in Scripture and the law of Christ rather than in an irreformable papal office.

Key Terms
Nominalism: The doctrine that only individual things exist in reality, while universals are merely names or mental/linguistic signs without independent extra-mental existence.
Ockham’s razor: A methodological maxim, associated with William of Ockham, that entities or explanatory principles should not be multiplied beyond [necessity](/terms/necessity/) in [metaphysics](/works/metaphysics/), science, or theology.
Universale (universal): In [medieval philosophy](/periods/medieval-philosophy/), a common nature or concept predicable of many; for Ockham, universals exist only as mental terms, not as real shared essences in things.
Suppositio (supposition theory): A medieval semantic theory, developed by Ockham, describing the way a term stands for (supponit pro) things in different contexts, underpinning his analysis of language and [logic](/topics/logic/).
Lingua mentalis (mental language): Ockham’s notion of an internal, structured system of mental terms that directly signify things and underlies spoken and written language, serving as the primary vehicle of thought.
Intuitiva cognitio (intuitive cognition): For Ockham, a kind of direct [knowledge](/terms/knowledge/) by which the intellect grasps the existence and certain properties of an individual object, contrasted with abstractive cognition of its features without affirming existence.
Abstractive cognition: A form of cognition that considers an object’s nature or features without determining whether the object exists, central to Ockham’s account of how we form universal concepts.
Potentia Dei absoluta / ordinata (absolute / ordained power of God): Ockham’s distinction between what God can do in principle (absolute power) and what God has in fact willed and bound Himself to do through His [laws](/works/laws/) and covenants (ordained power).
Voluntarism: A theological-philosophical view, emphasized by Ockham, that prioritizes God’s [free will](/topics/free-will/) in determining moral law and the created order over any necessary rational pattern discernible by human reason.
Via moderna (the “modern way”): A late medieval intellectual movement, strongly influenced by Ockham, characterized by nominalist metaphysics, refined logic, and a cautious, often skeptical [epistemology](/terms/epistemology/).
Plenitudo potestatis (fullness of power): A claim about the pope’s supreme authority in the church; Ockham criticizes expansive interpretations of this notion and argues for limits set by Scripture and law.
Franciscan poverty: The ideal of radical poverty and renunciation of property inspired by St Francis; Ockham defended a strict interpretation against papal attempts to moderate or redefine it.
Consequentia (consequence, logical consequence): In Ockham’s logic, a relation between propositions where one follows from another according to valid inferential rules, analyzed without appeal to real universals or forms.
Ens (being) and res (thing): Key scholastic metaphysical terms; for Ockham, ‘being’ and ‘thing’ refer primarily to individual substances and qualities rather than to universal entities or natures.
[Scholasticism](/periods/scholasticism/): The methodical, disputational style of medieval philosophy and theology practiced in universities, within which Ockham worked even as he critically revised its metaphysical commitments.
Intellectual Development

Franciscan Formation and Early Studies (c. 1300–1317)

During his novitiate and early studies in the Franciscan Order, likely in London and Oxford, Ockham absorbed the theological and philosophical legacy of Bonaventure and Duns Scotus, grounding himself in Aristotelian logic, metaphysics, and the Sentences tradition while beginning to question realist accounts of universals.

Oxford Sentences Commentaries and Systematic Thought (c. 1317–1323)

As a bachelor of theology lecturing on Peter Lombard’s Sentences, Ockham articulated many of his core philosophical positions: nominalist ontology, the primacy of intuitive cognition, his theory of supposition, and a rigorous account of divine omnipotence and freedom, earning a reputation as a daring and precise thinker.

Avignon Years and Logical Writings (1323–1328)

While under investigation at the papal court in Avignon, Ockham composed or revised major logical and philosophical works such as the Summa Logicae and Quodlibeta, refining his doctrines of mental language, signification, and parsimony in ontology, even as tensions with the papal curia intensified.

Exile and Political-Ecclesiological Writings (1328–c. 1342)

After fleeing Avignon to join Emperor Louis IV, Ockham shifted focus toward ecclesiology and political theory, arguing against papal infallibility and plenitudo potestatis, defending Franciscan poverty, and developing a theory of limited, law-bound authority for both church and empire.

Late Reflections and Influence (c. 1342–c. 1347)

In his final years in Munich, Ockham continued to defend his earlier positions and respond to critics, while his writings spread through European universities, catalyzing the rise of via moderna nominalism and reshaping debates about logic, metaphysics, and church–state relations.

1. Introduction

William of Ockham (c. 1287–c. 1347) was an English Franciscan friar, theologian, and philosopher whose work helped reshape late medieval scholasticism. Active primarily in Oxford, Avignon, and the imperial court at Munich, he is most commonly associated with nominalism and the methodological maxim later dubbed Ockham’s razor, often summarized as the injunction not to multiply entities or principles beyond necessity.

Ockham’s thought spans several domains. In metaphysics, he rejected robust realist accounts of universals, arguing that only individual substances and qualities exist extra-mentally and that universals are merely signs in thought and language. In logic and philosophy of language, he systematized a theory of supposition and developed a sophisticated account of mental language (lingua mentalis) that underlies spoken and written discourse. In epistemology, he distinguished sharply between intuitive and abstractive cognition, combining confidence in sensory-based knowledge of individuals with a cautious, sometimes skeptical attitude toward sweeping metaphysical claims.

Theologically, Ockham placed strong emphasis on divine omnipotence and voluntarism, drawing a clear line between what can be demonstrated by natural reason and what is known only by revelation. He also developed influential arguments about divine power and the contingency of the created order. Politically, his later writings criticized expansive papal claims to plenitudo potestatis and defended limits on ecclesiastical and secular power, contributing to later debates about church–state relations and constitutionalism.

Scholars differ on how radical Ockham was: some portray him as a decisive break from high scholastic realism and a precursor of modern empiricism and secular politics; others emphasize continuities with earlier Franciscan thought and stress his commitment to orthodox doctrine. His work became a cornerstone of the via moderna in late medieval universities and continues to be a major point of reference in discussions of medieval logic, metaphysics, theology, and political theory.

2. Life and Historical Context

Biographical Outline

Most details of Ockham’s life are reconstructed from scattered documentary references and internal evidence from his works. He was likely born around 1287 in Ockham, Surrey (England). He entered the Franciscan Order as a youth, studied in England (probably at the London studium and then Oxford), and lectured on Peter Lombard’s Sentences around 1317–1319. He never completed the formal requirements for the doctorate in theology, which earned him the title Venerabilis Inceptor (“Venerable Beginner”) rather than doctor.

In 1323 he was summoned to Avignon, seat of the papal court, to answer charges of doctrinal error. There he spent several years under investigation while composing major logical and philosophical treatises. In 1328, amid escalating conflicts between Pope John XXII and the Franciscan leadership, Ockham fled Avignon with the minister general Michael of Cesena and sought protection from Emperor Louis IV of Bavaria, first in Pisa and later in Munich. He spent his remaining years in imperial territory, producing extensive political and ecclesiological writings, and probably died during a plague outbreak around 1347.

Historical and Intellectual Setting

Ockham worked within late scholasticism, a period marked by intensive engagement with Aristotle, the established commentary tradition, and intra-scholastic disputes. He inherited a landscape shaped by Thomas Aquinas, Henry of Ghent, and especially John Duns Scotus, whose sophisticated realism and metaphysics of formal distinction he would critically revise.

Politically and ecclesiastically, Ockham’s career unfolded during the Avignon Papacy and amid tensions between papal and imperial authority. Disputes over Franciscan poverty, papal claims to plenary power, and the boundary between spiritual and temporal jurisdiction formed the backdrop of his exile. His political writings respond directly to these controversies, but they also reflect broader debates about canon law, conciliarism, and the nature of sovereignty in the Holy Roman Empire.

The reception of Ockham’s ideas occurred in a university environment increasingly divided between the older via antiqua (associated with realist metaphysics) and the emerging via moderna, within which his positions on logic, language, and ontology became central reference points.

3. Franciscan Formation and Oxford Years

Entry into the Order and Early Training

Ockham’s entry into the Franciscans around 1300–1309 placed him within a tradition emphasizing evangelical poverty, affective devotion, and a distinctive theological perspective. He likely underwent basic training in grammar, logic, and philosophy at the London Franciscan studium, where Aristotelian texts and commentaries by figures such as Bonaventure and Scotus were standard.

Franciscan education stressed both fidelity to the Rule of St Francis and engagement with contemporary scholastic debates. Ockham’s later writings suggest familiarity with intra-Franciscan tensions over poverty and obedience, which would later color his political and ecclesiological positions.

Oxford Studies and Sentences Lectures

By the late 1310s, Ockham was at Oxford, serving as a bachelor of theology and lecturing on Peter Lombard’s Sentences, the core theological textbook. His Ordinatio (revised commentary) and Reportatio (student report) on the four books of the Sentences preserve much of his early systematic thought.

Key themes emerge during this period:

  • A developing nominalist stance on universals and categories of being.
  • A refined theory of supposition and early reflections on mental terms.
  • A methodological emphasis on parsimony and scriptural warrant in theology.
  • Doctrines on divine power, grace, and the sacraments that later drew suspicion.

Ockham did not proceed to the doctoral degree at Oxford, possibly owing to intra-order politics or emerging controversies about his teachings. This unfinished status is reflected in his honorary title Venerabilis Inceptor rather than magister.

Intellectual Milieu at Oxford

Oxford in Ockham’s time was a vibrant center of logical and theological innovation, with strong Franciscan and Merton College traditions in natural philosophy and mathematics. Ockham’s views developed in conversation, and sometimes in tension, with:

  • Duns Scotus and his followers, whose subtle distinctions Ockham frequently criticized.
  • English logicians exploring obligationes, consequences, and semantic theories.
  • Dominican and secular masters defending various forms of moderate realism.

Scholars disagree on how integrated Ockham was into specific Oxford schools, but there is broad agreement that his Oxford years formed the crucible for the logical and metaphysical positions that would later define him.

4. Avignon, Condemnation, and Exile

Summons to Avignon and Investigation

In 1323, Ockham was ordered to appear before the papal court at Avignon to answer accusations of doctrinal error, particularly concerning his teaching in the Sentences and related works. The precise list of charges is not fully preserved, but later accounts point to disputes over:

  • The nature of universals and knowledge of God.
  • Aspects of ecclesiology and sacramental theology.
  • His strong emphasis on divine omnipotence and contingency.

At Avignon, Ockham lived under a form of supervised residence for several years while theologians examined his writings. During this period he composed or revised major logical works, including the Summa Logicae and Quodlibeta, which circulated beyond the papal curia.

Conflict over Franciscan Poverty

Simultaneously, the papacy under John XXII was embroiled in a controversy with the Franciscan Order over the doctrine of evangelical poverty—specifically, whether Christ and the apostles owned property. The Franciscan minister general Michael of Cesena defended a strict interpretation denying ownership, while John XXII rejected this as heretical.

Ockham, already at Avignon, came to side with Michael and the “Spiritual” interpretation of Franciscan poverty. He studied papal bulls and canon law, concluding that John XXII’s position conflicted with earlier papal decisions and, in his view, with the Gospel.

Flight and Exile with the Emperor

In 1328, fearing condemnation and convinced that the pope had fallen into heresy, Ockham fled Avignon with Michael of Cesena and other allies. They sought protection from Emperor Louis IV of Bavaria, who was then in conflict with John XXII over imperial rights.

Ockham reportedly declared: “I appeal from you, John, to a future general council,” symbolizing his break with papal authority as then exercised.

Settling eventually in Munich, Ockham entered a long period of exile under imperial protection. There he devoted himself to extensive political and ecclesiological writings, attacking papal claims to plenitudo potestatis and defending the Franciscan understanding of poverty as well as the autonomy of secular rulers.

Condemnations and Aftermath

Ockham himself was never subjected to a formal, comprehensive doctrinal condemnation comparable to that of some contemporaries, though specific propositions associated with his thought were criticized in university statutes and later censures. His continued status vis-à-vis the Franciscan Order and the papacy remained irregular.

Historians debate whether his exile radically altered his intellectual trajectory or simply redirected it. Some emphasize continuity between his Oxford theology and his later political arguments; others see the Avignon crisis as a decisive turning point that pushed him toward more systematic critiques of ecclesiastical authority.

5. Major Works and Their Transmission

Principal Works

Ockham’s surviving corpus spans logic, theology, and political theory. Key works include:

DomainWork (Latin / English)Approx. DateNotes on Content
TheologyOrdinatio & Reportatio on the Sentencesc. 1317–1322Core doctrinal and philosophical views; based on Oxford lectures.
LogicSumma Logicae (Sum of Logic)c. 1323–1326Systematic treatise on terms, supposition, consequences, and sophisms.
Logic/TheologyQuodlibeta septem (Seven Quodlibetal Questions)c. 1322–1324Public disputations covering a range of theological and philosophical questions.
Exegesis/LogicExpositiones on Porphyry, Categories, On Interpretationc. 1318–1323Commentaries integrating logical theory with Aristotelian texts.
EcclesiologyDialogus (Dialogus de potestate papae)c. 1332–1342Dialogue on papal power, heresy, and church governance.
Political TheoryDe imperatoris et pontificis potestatec. 1338–1340On the respective powers of emperor and pope.
PovertyOpus nonaginta dierum (Work of Ninety Days)c. 1332–1334Defense of Franciscan poverty and critique of papal teaching.
Papal PowerOcto quaestiones de potestate papaec. 1339–1342Eight questions focusing on limits of papal authority.

Scholars generally accept the authenticity of these works, though some minor treatises and letters are debated.

Manuscript Tradition and Early Reception

Ockham’s writings circulated widely in manuscript form in the later 14th and 15th centuries, especially in university centers such as Paris, Oxford, and Cologne. His logical works, particularly the Summa Logicae, were copied extensively and used for teaching within the via moderna; they influenced generations of logicians and philosophers.

The theological and political writings had a more complex transmission. The Dialogus and related political works often circulated in partial or abridged versions and were sometimes transmitted anonymously or under generic rubrics (e.g., “tractatus de potestate papae”), leading to later uncertainties about attribution and dating.

With the advent of printing, selected logical works appeared early in the 16th century, but comprehensive critical editions are largely a product of modern scholarship. Major modern editorial projects include:

  • Critical editions of the Ordinatio and Reportatio by various scholarly teams.
  • The Opera Politica series, assembling the political and ecclesiological writings.
  • Modern Latin and bilingual editions of the Summa Logicae and Aristotelian commentaries.

These editions have enabled more precise study of Ockham’s development and the relationship between his Oxford, Avignon, and Munich writings, though debates remain about the chronology of some texts and their internal revisions.

6. Method, Ockham’s Razor, and Theological Commitments

Methodological Principles

Ockham’s approach combines logical rigor with a distinctive view of the sources of certainty. A programmatic statement appears in the Ordinatio:

“Nothing ought to be posited without a reason, unless it is self-evident or known by experience or established by the authority of Sacred Scripture.”

— William of Ockham, Ordinatio I, dist. 30, q. 1

He distinguishes:

  • Evident principles of reason (e.g., logical truths).
  • Empirical knowledge grounded in intuitive cognition.
  • Revealed truths accepted on the authority of Scripture.

Non-evident metaphysical postulates lacking support from these sources are treated with suspicion.

Ockham’s Razor

The principle commonly called Ockham’s razor condenses his methodological economy. A canonical formulation is paraphrased as:

“Plurality is not to be posited without necessity.”

— Paraphrase of Ockham’s methodological maxim; cf. Summa Logicae I, c. 12

Ockham deploys this maxim in several ways:

  • Ontological parsimony: rejecting extra entities such as real universals, species, or intermediary forms when explanatory work can be done by individuals and their qualities.
  • Explanatory restraint: preferring simpler accounts of mental and linguistic phenomena that appeal to fewer kinds of entities or relations.
  • Theological caution: avoiding speculative constructions (e.g., elaborate hierarchies of forms) not required by Scripture or evident reason.

Commentators debate whether the razor is primarily an epistemic principle (minimizing unjustified assumptions), an ontological thesis (affirming a sparse ontology), or a methodological rule of thumb. Many agree that in Ockham’s practice these aspects are closely intertwined.

Theological Commitments and Constraints

Ockham insists that theology is grounded in revelation rather than in demonstrative science. He holds that central Christian doctrines—such as the Trinity, Incarnation, and Eucharist—cannot be strictly proved by natural reason, even if they are not contrary to it.

“God cannot be proved to exist by any evident proposition of reason, yet His existence is most certain through faith.”

— William of Ockham, Ordinatio I, dist. 2, q. 3

He thereby separates the domains of philosophy and theology while allowing philosophical tools to clarify revealed truths without claiming to demonstrate them.

Scholars differ on how radical this separation is. Some see in Ockham an early form of fideism; others emphasize that he still uses philosophical argumentation extensively in theology, but under the constraint that speculative claims may not override clear scriptural testimony.

In ethical and ecclesiological matters, Ockham holds that God’s will, as expressed in Scripture and right reason, sets binding norms. His methodological suspicion toward unnecessary postulates also informs his critique of expansive claims to ecclesiastical authority that, in his view, lack clear scriptural or rational grounding.

7. Metaphysics and Nominalism

Ontological Commitments

Ockham’s metaphysics is often characterized as a strict nominalism, though interpretations vary. At its core is the claim that only individual entities (singular substances and their particular qualities or actions) exist in the extra-mental world. Universal natures or forms are denied independent reality.

Key terms such as ens (being) and res (thing) apply, in Ockham’s view, primarily and univocally to individuals, not to overarching essences. He rejects real distinctions beyond those grounded in distinct individual entities or in clearly different intrinsic properties.

Universals and Mental Signs

Ockham’s best-known thesis in metaphysics concerns universals. He denies that there are real common natures shared by many individuals either:

  • As entities existing outside the mind (extra animam), or
  • As distinct qualitative forms in the soul.

Instead, universals are mental terms or concepts that can be predicated of many individuals:

“A universal is not something outside the soul existing in individual things, nor something existing in the soul as a quality; rather, it is only a mental term signifying many things.”

— William of Ockham, Ordinatio I, dist. 2, q. 8

On this account, the unity of a universal lies in the single act of understanding that can refer to many, not in a shared metaphysical essence.

Rejection of Excessive Entities and Distinctions

Ockham systematically employs his parsimonious method to critique various scholastic constructs, including:

  • Substantial forms beyond the minimal required for explaining natural change.
  • Habits and powers postulated as distinct entities when they may be reducible to the soul or to acts.
  • The formal distinction of Scotus, which posits intermediate distinctions between real and purely conceptual ones.

He tends to reduce such items either to the subject itself (e.g., the soul) or to its individual qualities and acts, provided explanatory adequacy is preserved.

Causality, Individuation, and Modality

In causality, Ockham upholds efficient causes while eschewing robust metaphysical frameworks of final causes and substantial forms, arguing that many explanatory roles attributed to them can be handled by laws of nature and divine concourse.

On individuation, he rejects theories positing an individuating “haecceity” (thisness). For Ockham, individuality is primitive: each entity is this individual simply by being numerically distinct, without an added individuating principle.

Regarding modality, he emphasizes the contingency of created reality, connecting metaphysical possibility and necessity to divine power and will rather than to an independently structured realm of essences. Critics contend that this undercuts the stability of natural kinds; proponents argue that it underscores the dependence of creation on God.

Assessments of Ockham’s Nominalism

Historians disagree on whether Ockham should be read as an extreme nominalist, a conceptualist, or a moderate realist about certain structures. Some stress that his recognition of stable mental concepts and natural similarities among individuals preserves a form of order akin to moderated realism. Others emphasize his rejection of universals and many traditional metaphysical entities as marking a significant departure from high scholastic realism.

8. Logic, Language, and Mental Terms

Logic as Instrument and Science

For Ockham, logic is both an instrument for correct reasoning and a theoretical discipline concerned with the properties of terms, propositions, and inferences. His Summa Logicae offers a systematic account encompassing:

  • Terms and categoremata/syncategoremata
  • Supposition theory
  • Consequences (consequentiae) and syllogistic
  • Treatment of fallacies and sophisms

Logical analysis is carried out with minimal ontological commitments, in line with his nominalist metaphysics.

Supposition Theory

Central to Ockham’s semantics is suppositio (supposition), the way a term “stands for” things in a given context. He distinguishes, among others:

  • Personal supposition: a term stands for the individuals it signifies (“man” for particular men).
  • Simple supposition: a term stands for a concept or term (“‘man’ is a species”).
  • Material supposition: a term stands for itself as a word (“‘man’ has three letters”).

This framework allows detailed analysis of quantification, reference, and scope in natural language and scholastic Latin.

Mental Language (Lingua mentalis)

Ockham posits an internal mental language composed of simple and complex concepts or mental terms that directly signify things. Spoken and written languages are conventional signs built upon this natural mental system.

Features of mental language include:

  • Structured syntax paralleling that of spoken propositions.
  • Natural signification: concepts signify their objects not by convention but by a natural relation arising from cognition.
  • Universality: all rational beings share, in principle, the same mental language, even though their spoken tongues differ.

This theory allows Ockham to explain meaning and inference without positing extramental universals: the primary bearers of logical properties are propositions in mental language.

Consequences and Inference

Ockham provides a refined account of logical consequence (consequentia). He distinguishes, for example:

  • Formal consequences: valid in virtue of logical form alone.
  • Material consequences: depend also on contingent truths about the world.

His analysis covers conditionals, modal propositions, and inferences involving terms with different kinds of supposition. Later medieval logicians built extensively on Ockham’s classifications and tests for validity.

Interpretative Debates

Scholars discuss whether Ockham’s mental language implies a kind of conceptual realism (since concepts have structured roles and necessary relations) or reinforces strict nominalism by treating concepts as acts without additional ontological status. Others examine the extent to which his theory anticipates later ideas about logical form, semantic content, and internal representation in the philosophy of mind and language.

9. Epistemology and Theories of Cognition

Intuitive and Abstractive Cognition

Ockham distinguishes two primary types of cognition:

  • Intuitive cognition (intuitiva cognitio): a direct awareness of an individual object that includes, in normal cases, knowledge of its existence and certain contingent features.
  • Abstractive cognition: consideration of an object’s nature or properties without determining whether the object exists.

Intuitive cognition grounds our knowledge of present singulars and provides the basis for empirical science. Abstractive cognition allows us to think about non-existent or merely possible objects and underlies the formation of universal concepts.

Knowledge of the External World

Ockham maintains that intuitive cognition, under ordinary circumstances, yields certain knowledge of present external objects and their states. This confidence is partly rooted in his theological conviction that God, as truthful and omnipotent, does not habitually deceive creatures in their basic cognitive operations.

Nevertheless, he acknowledges logical possibilities in which God could cause an intuitive cognition without a corresponding object (e.g., in a miraculous deception). Some interpreters see in this an early form of epistemic skepticism; others argue that Ockham treats such scenarios as merely hypothetical and not undermining everyday certainty.

Concepts and Mental Acts

For Ockham, concepts are mental acts rather than distinct entities or species. They function as natural signs of things, emerging through cognitive processes involving intuitive and abstractive cognition. The mind can form complex concepts and combine them into propositions within mental language.

This view avoids positing intelligible species or intermediary entities mediating between mind and object. Instead, the direct relation of cognition to objects, especially in intuitive awareness, is emphasized.

Scientific and Theological Knowledge

Ockham distinguishes between:

  • Scientia (scientific knowledge) in the Aristotelian sense: demonstrative knowledge of necessary connections, primarily within mathematics and certain aspects of natural philosophy.
  • Opinion or probable belief about contingent matters.
  • Faith, grounded in revelation, which may concern truths not accessible to natural reason.

He is cautious about claims to necessary knowledge in theology and much of natural philosophy, often relegating them to the realm of faith or probable reasoning due to the pervasive contingency of created reality under God’s absolute power.

Debates on Ockham’s Epistemology

Interpretations divide on the extent of Ockham’s empiricism and skeptical tendencies. Some emphasize his reliance on intuitive cognition and experience as anticipating modern empiricist epistemology. Others highlight his insistence that many traditional metaphysical and theological claims cannot be demonstrated, seeing in this a limiting of reason’s scope rather than a thoroughgoing skepticism about ordinary knowledge.

10. Theology, Divine Power, and Voluntarism

Divine Omnipotence and the Two Powers of God

Ockham develops a nuanced account of divine power, distinguishing:

  • Absolute power (potentia Dei absoluta): what God could do, considered simply as omnipotent, unconstrained by the current order.
  • Ordained power (potentia Dei ordinata): what God actually wills and does according to the existing order of creation and the laws He has freely established.

This distinction allows Ockham to affirm that God could have created different worlds, different natural laws, or different economies of salvation, while maintaining that in fact God has chosen a specific, contingent order.

Voluntarism and Moral Law

Ockham is often described as a leading proponent of voluntarism, the view that God’s will is primary in determining moral and legal norms. He holds that:

  • Certain moral precepts (e.g., love of God) are necessary given God’s nature.
  • Many other moral rules (e.g., specific property arrangements or ceremonial laws) are contingent on God’s free commands and could have been otherwise.

This position supports his emphasis on the freedom of God and the contingency of created institutions. Critics argue that it risks making morality arbitrary; defenders contend that Ockham still anchors key norms in God’s good and wise will.

Grace, Predestination, and Merit

In soteriology, Ockham aligns with the broader scholastic tradition while stressing divine freedom. He affirms:

  • The necessity of grace for salvation.
  • That God freely establishes the conditions under which human acts become meritorious.
  • That predestination is grounded in God’s will, foreknowing but not coercing human free choices.

Ockham often frames these doctrines with reference to the distinction between God’s absolute and ordained power, underscoring that the present economy of salvation is contingent on divine decision.

Theology and the Limits of Reason

Ockham insists on the non-demonstrability by natural reason of many central Christian doctrines, including the Trinity and Incarnation. They are accepted on the authority of Scripture and the Church, not on philosophical proof.

He also applies parsimony to theology: speculative constructions not clearly warranted by revelation or necessary reasoning are avoided. For instance, he is critical of elaborate metaphysical explanations of the Eucharist that go beyond the requirements of faith and ecclesial teaching.

Interpretations of Ockham’s Voluntarism

Scholars diverge on how far Ockham’s voluntarism extends. Some see it as radical, making almost all moral and natural order contingent on arbitrary divine choice. Others argue that Ockham preserves significant constraints in God’s nature (e.g., truthfulness, goodness) and that his emphasis on will primarily guards against subordinating God to independently necessary patterns of rationality.

In contemporary discussions, Ockham’s views on divine power and law continue to be central reference points in debates about divine command theory, moral realism, and the relation between theology and philosophy.

11. Ethics, Law, and Moral Theory

Natural Law and Divine Commands

Ockham’s ethical thought is closely connected to his theology of divine will. He holds that natural law consists of moral principles that are, in part, knowable by reason but ultimately grounded in God’s commands.

He distinguishes:

  • Necessary precepts: such as the obligation to love God above all, which follow from God’s nature and cannot be otherwise.
  • Contingent precepts: many specific moral and legal norms that God could have legislated differently.

This leads many interpreters to classify Ockham as a representative of divine command ethics, though debates persist about the extent to which he allows independent rational insight into moral goodness.

Human Freedom and Responsibility

Ockham affirms robust freedom of the will. The human will can choose between alternatives, including contrary moral options, even in the presence of strong inclinations. This freedom underwrites moral responsibility and the possibility of merit or demerit.

He emphasizes that God, in the present ordained order, has bound Himself to reward certain acts and dispositions (e.g., acts performed in charity) and to punish others, though in absolute power God could have arranged matters otherwise.

Property, Poverty, and Use of Goods

In debates over Franciscan poverty, Ockham develops a detailed analysis of property rights and use. He distinguishes:

  • Dominion (ownership): legal right to dispose of goods.
  • Use (usus): factual enjoyment of goods without ownership.

He argues, in line with the stricter Franciscan position, that it is possible to have use without ownership, and that evangelical perfection can involve the renunciation of property. At the same time, he acknowledges the legitimacy of secular property arrangements as part of the ordained order willed by God.

These reflections contribute to a broader theory of positive law, custom, and natural right, used later in his political writings.

Law, Conscience, and Authority

For Ockham, law is fundamentally a product of the will of a superior (ultimately God) binding inferiors. Human and ecclesiastical laws derive their authority either from divine delegation or from rationally-warranted communal decisions consistent with divine law.

He grants a significant role to conscience: individuals must obey God rather than human authorities if the latter command what is contrary to divine law. This plays a role in his defense of resistance to papal commands perceived as violating Christ’s teaching.

Interpretative Issues

Scholars debate:

  • Whether Ockham allows any intrinsic moral values accessible to reason independently of divine commands.
  • How his analysis of property and use relates to emerging notions of subjective rights in late medieval legal theory.
  • The extent to which his stress on freedom and divine legislation anticipates later contractualist or rights-based ethical frameworks.

While there is no consensus on these questions, Ockham’s ethical and legal reflections are widely recognized as significant for the evolution of medieval theories of law, rights, and moral obligation.

12. Political Philosophy and Critique of Papal Authority

Context: Empire, Papacy, and Franciscan Poverty

Ockham’s political writings emerge from concrete conflicts: the struggle between Emperor Louis IV and Pope John XXII, and the controversy over Franciscan poverty. His works such as the Dialogus, De imperatoris et pontificis potestate, and Octo quaestiones address broader issues of sovereignty, church governance, and limits on authority.

Limits of Papal Power

Ockham contests expansive claims that the pope possesses plenitudo potestatis (fullness of power) over both spiritual and temporal matters. He argues that:

  • The pope’s authority is ministerial, not absolute, and derived from Christ and the Church.
  • The pope can err, even in matters of faith, when departing from Scripture and the tradition of the Church.

“The pope can err, even in matters of faith and morals, when he does not adhere to the rule of Scripture and the teaching of Christ.”

— William of Ockham, Dialogus, Part III, Tract I

Ockham maintains that a pope who persistently teaches heresy or abuses power can be resisted and, under certain conditions, deposed by the Church, often represented through a general council.

Authority of Councils and the Community

Ockham gives a significant role to the universitas fidelium (community of the faithful) and to general councils as expressions of the Church’s ultimate authority under Christ. While not fully developing a systematic conciliarism, he provides arguments later used by conciliarist thinkers to justify the superiority of councils over a wayward pope.

He also emphasizes the role of canon law, tradition, and earlier papal decisions as constraints on current papal action, arguing that popes are bound by prior legitimate determinations.

Secular Power and the State

In relation to the state and secular rulers, Ockham holds that:

  • Secular authority stems from God but is mediated through the people or political community.
  • The emperor and kings have independent jurisdictions not subject to direct papal control in temporal matters, except in extraordinary cases.

He defends the right of secular rulers to govern civil affairs, levy taxes, and administer justice without papal interference, as long as they do not contravene divine law.

This position supports a clearer distinction between spiritual and temporal power, anticipating later theories of limited government and church–state separation, though framed within a medieval Christian context.

Resistance and Obedience

Ockham’s own resistance to John XXII informs his theoretical reflections. He argues that Christians must disobey commands from ecclesiastical superiors that are manifestly contrary to Scripture or right reason. However, he also stresses ordinary obligations of obedience to legitimate authority in both church and state when acting within its proper bounds.

Interpretations and Influence

Scholars differ on how far Ockham’s political thought anticipates modern constitutionalism or rights theory. Some see him as an early architect of limited, law-bound authority and a source for later notions of popular sovereignty. Others caution that his primary aim was the defense of traditional doctrine and Franciscan poverty against what he considered papal innovation, rather than a systematic political liberalism.

Nevertheless, his analyses of papal fallibility, council authority, and the distinction between spiritual and temporal powers were influential in late medieval disputes and beyond.

13. Relation to Earlier Scholastics and the Via Moderna

Engagement with Earlier Scholastics

Ockham’s thought develops in dialogue with earlier scholastic figures:

ThinkerAspect Engaged by OckhamOckham’s Typical Response
Thomas AquinasModerate realism, natural theologyCritiques proofs of God’s existence; rejects real universals.
Henry of GhentIlluminationism, unicity of truthOpposes special divine illumination as necessary for certainty.
Duns ScotusFormal distinction, haecceities, univocityRejects formal distinction and haecceities; adapts univocity of being.
Giles of RomeStrong papal monarchyChallenges plenitudo potestatis; limits papal power.

Ockham often admires Scotus’s rigor yet targets Scotistic metaphysical constructs such as formal distinctions and haecceities as unnecessary entities. He shares with Scotus a univocal concept of being, but uses it within a more parsimonious ontology.

He opposes Henry of Ghent’s reliance on divine illumination for certain knowledge, favoring a more naturalistic account grounded in intuitive cognition.

From Via Antiqua to Via Moderna

In the 14th and 15th centuries, scholastic thought was often divided between the via antiqua (“old way”) and via moderna (“modern way”). The via antiqua was associated with realist metaphysics (Aquinas, Scotus, some Thomists and Scotists), while the via moderna emphasized nominalist or conceptualist approaches.

Ockham became a key reference point for the via moderna, particularly in:

  • Logic: his Summa Logicae and semantic theories were widely taught.
  • Metaphysics: the denial of real universals and reduction of ontological categories.
  • Epistemology: stress on intuitive cognition and limits of demonstrative knowledge.

Later thinkers such as John Buridan, Marsilius of Inghen, and Gabriel Biel adopted and adapted Ockhamist themes, though they also modified or criticized aspects of his system.

Continuities and Breaks

Historians debate whether Ockham marks a sharp break with the scholastic tradition or represents an internal development. Some emphasize:

  • Continuity: he shares many scholastic methods, accepts core doctrines, and works within the Sentences commentary framework.
  • Innovation: his consistent application of parsimony and critique of realist metaphysics produce a significantly different intellectual landscape.

The extent to which the via moderna should be seen as a “school” versus a loose family of thinkers influenced by Ockham is also contested. While university statutes sometimes distinguished Ockhamist or nominalist positions from Thomist or Scotist ones, there was considerable diversity within each camp.

Retrospective Assessments

In early modern and modern historiography, Ockham has been variously portrayed as:

  • A destroyer of metaphysics and the high scholastic synthesis.
  • A reformer who purified scholasticism of speculative excess.
  • A transitional figure bridging medieval and modern thought.

Contemporary scholarship tends to present a more nuanced picture, situating Ockham firmly within the scholastic tradition while acknowledging his significant role in shaping the via moderna and subsequent philosophical developments.

14. Reception, Controversies, and Misattributions

Immediate and Late Medieval Reception

Ockham’s ideas spread quickly in the 14th century, especially through his logical works. University curricula in Paris, Oxford, and German centers incorporated Ockhamist or nominalist texts, sometimes alongside Thomist or Scotist materials. His influence was particularly strong in:

  • Logic and semantics: shaping discussions of supposition, consequence, and mental language.
  • Metaphysics: prompting debates over universals and individuation.
  • Theology: stimulating responses to his views on divine power and the limits of reason.

At the same time, some university statutes and condemnations targeted propositions associated with Ockham or “modern” theologians, reflecting concern about perceived doctrinal or philosophical implications of his ideas.

Controversies and Criticisms

Ockham’s positions provoked criticism on multiple fronts:

  • Realist theologians argued that his nominalism undermined the intelligibility of theology and natural law.
  • Opponents of voluntarism contended that his emphasis on divine will threatened the stability of moral norms.
  • Supporters of strong papal monarchy accused his political writings of fostering disobedience and weakening church unity.

Specific doctrinal points—such as his views on intuitive cognition, the non-demonstrability of God’s existence, or the possibility of divine deception—were scrutinized and sometimes censured in local academic contexts, though he was not the subject of a single, definitive papal condemnation.

Ockham in the Early Modern Period

In the 16th and 17th centuries, Ockham’s name continued to be associated with the via moderna, especially among certain late scholastic theologians (e.g., Gabriel Biel) who transmitted and modified his ideas. Reformers and humanists occasionally referenced Ockham, sometimes approvingly for his critiques of papal power, sometimes dismissively as emblematic of scholastic subtleties.

His logical and metaphysical doctrines were both utilized and attacked in early modern philosophy. Some historians see echoes of Ockhamist parsimony and skepticism about universals in thinkers such as Hobbes or Locke, though the direct lines of influence are debated.

Misattributions and the “Razor”

Over time, various views and sayings have been attributed to Ockham with uncertain or no textual basis. The phrase “entities must not be multiplied beyond necessity” is widely linked to him, though its exact wording does not occur in his extant works; rather, it condenses themes and scattered formulations present in his writings.

Some political and theological tracts circulated under his name in the later Middle Ages and early modern period that modern scholarship regards as spurious or of doubtful authorship. Conversely, several anonymous works once detached from him have been tentatively reattributed on the basis of style, doctrine, and manuscript evidence, though such attributions often remain contested.

Modern Scholarship

From the 19th century onward, critical editions and systematic studies reshaped understanding of Ockham. Different interpretive schools highlight:

  • His role as a precursor of empiricism and analytic philosophy (with emphasis on logic and language).
  • His contribution to theology and debates on divine power.
  • His significance in political thought and ecclesiology.

Disagreements persist about how to integrate these facets into a single picture and about the extent to which later “Ockhamism” accurately reflects his own positions versus developments by successors.

15. Legacy and Historical Significance

Impact on Medieval and Early Modern Thought

Ockham’s legacy in the late Middle Ages is closely tied to the rise of the via moderna. His logical works became standard teaching texts, shaping scholastic logic and semantics for centuries. His nominalist metaphysics and epistemological caution influenced a broad range of thinkers, including John Buridan and Gabriel Biel, contributing to shifts in how universals, causality, and scientific knowledge were conceived.

In political and ecclesiological debates, his critiques of papal plenitude of power and his defense of conciliar and secular authority informed later conciliarist theorists and discussions of church reform. Elements of his thought resurfaced, sometimes indirectly, in early modern controversies over sovereignty, religious authority, and the relation between church and state.

Contributions to Later Philosophy

Historians of philosophy often identify Ockham as a significant forerunner of aspects of modern philosophy:

  • In metaphysics, his parsimonious ontology prefigures later strategies that limit ontological commitments to what is empirically or logically required.
  • In epistemology, his emphasis on intuitive cognition and skepticism regarding speculative metaphysics anticipates some themes of early modern empiricism.
  • In philosophy of language and logic, his analysis of mental language and logical form resonates with later concerns in analytic philosophy.

The degree of direct historical influence versus retrospective affinity remains debated, but his work serves as an important point of comparison.

Theological and Ethical Legacy

Within theology, Ockham’s articulation of divine omnipotence, the absolute/ordained power distinction, and voluntarist accounts of moral law continue to shape discussions in philosophical theology and ethics, particularly in relation to divine command theory and the problem of contingency in moral norms.

His insistence on the distinction between what can be demonstrated by reason and what belongs to faith has been seen as a precursor to later efforts to clarify the boundaries between philosophy and theology.

Continuing Debates

Ockham’s historical significance is itself a subject of scholarly debate. Competing assessments present him as:

  • A disruptive innovator whose critiques contributed to the fragmentation of the high scholastic synthesis.
  • A conservative Franciscan theologian whose primary aim was to defend orthodoxy and evangelical poverty while refining scholastic methods.
  • A transitional figure whose work both culminates medieval scholasticism and prepares intellectual shifts characteristic of the early modern period.

These different narratives reflect broader questions about the continuity or rupture between medieval and modern thought.

Modern Relevance

Today, Ockham is studied across multiple disciplines—philosophy, theology, intellectual history, and political theory. His methodological maxim, Ockham’s razor, is frequently invoked (often in simplified form) in scientific and philosophical contexts as a heuristic for theory choice. His detailed analyses of language, cognition, and law continue to attract attention in specialized scholarship, while his life and controversies offer a window into the complex interplay of ideas, institutions, and power in the late Middle Ages.

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BibTeX
@online{philopedia_william_of_ockham,
  title = {William of Ockham},
  author = {Philopedia},
  year = {2025},
  url = {https://philopedia.com/philosophers/william-of-ockham/},
  urldate = {December 10, 2025}
}

Note: This entry was last updated on 2025-12-08. For the most current version, always check the online entry.

Study Guide

intermediate

The biography expects some familiarity with medieval philosophy and theology, but it is written to be accessible to advanced undergraduates or interested general readers. Students with no prior exposure may need to pause frequently to look up technical terms and historical context.

Prerequisites
Required Knowledge
  • Basic structure of medieval Western Christianity (papacy, religious orders, universities)The biography assumes familiarity with the roles of the pope, religious orders like the Franciscans, and university theology faculties in the 13th–14th centuries.
  • Introductory logic and philosophical vocabulary (e.g., proposition, inference, metaphysics, epistemology)Ockham’s significance lies largely in logic, metaphysics, and epistemology; understanding these basic terms is necessary to follow discussions of his innovations.
  • General overview of scholasticism and Aristotle’s influence on medieval philosophyThe entry frequently compares Ockham to earlier scholastics such as Aquinas and Duns Scotus and presupposes awareness of the Aristotelian commentary tradition.
  • Basic medieval European political history (Holy Roman Empire vs. papacy, Avignon Papacy)Ockham’s exile and political writings are rooted in conflicts between Pope John XXII and Emperor Louis IV, which are easier to follow with this background.
Recommended Prior Reading
  • ScholasticismProvides the intellectual and institutional context—methods, genres (like Sentences commentaries), and main debates—within which Ockham worked.
  • John Duns ScotusOckham develops many of his views in response to Scotus’s realism, formal distinctions, and theology; knowing Scotus clarifies what Ockham is rejecting or revising.
  • The Avignon PapacyExplains the political-ecclesiastical background (papal residence in Avignon, conflicts with the empire, Franciscan poverty controversy) that shaped Ockham’s exile and political thought.
Reading Path(difficulty_graduated)
  1. 1

    Skim for a narrative overview of Ockham’s life and why he matters.

    Resource: Sections 1–2 (Introduction; Life and Historical Context)

    30–40 minutes

  2. 2

    Focus on Ockham’s career stages and major texts, taking brief notes on dates and locations.

    Resource: Sections 3–5 (Franciscan Formation and Oxford Years; Avignon, Condemnation, and Exile; Major Works and Their Transmission)

    45–60 minutes

  3. 3

    Build conceptual foundations by studying his method, nominalism, and logic/language theory using the glossary alongside the text.

    Resource: Sections 6–8 plus relevant glossary terms (Nominalism, Ockham’s razor, Universale, Suppositio, Lingua mentalis)

    1.5–2 hours

  4. 4

    Deepen understanding of his epistemology and theology and connect them to his view of divine power and voluntarism.

    Resource: Sections 9–11 (Epistemology and Theories of Cognition; Theology, Divine Power, and Voluntarism; Ethics, Law, and Moral Theory)

    1.5–2 hours

  5. 5

    Study his political philosophy and his relation to other scholastics, noting continuities and breaks with the broader tradition.

    Resource: Sections 12–13 (Political Philosophy and Critique of Papal Authority; Relation to Earlier Scholastics and the Via Moderna)

    1–1.5 hours

  6. 6

    Synthesize what you’ve learned by examining his reception, common misconceptions, and long-term legacy; then answer discussion questions.

    Resource: Sections 14–15 (Reception, Controversies, and Misattributions; Legacy and Historical Significance) plus the ‘Essential Quotes’ and glossary

    1–1.5 hours

Key Concepts to Master

Nominalism

The view that only individual substances and their particular qualities exist in reality, while universals are merely mental or linguistic signs without independent extra-mental existence.

Why essential: Ockham’s rejection of real universals underpins his metaphysics, logic of terms, and his use of Ockham’s razor to cut away unnecessary entities.

Ockham’s razor

A methodological maxim associated with Ockham, often summarized as ‘plurality is not to be posited without necessity,’ which counsels against multiplying entities or principles beyond what is needed to explain phenomena.

Why essential: This principle structures Ockham’s approach across metaphysics, theology, and politics; understanding it explains why he criticizes many traditional scholastic distinctions.

Universale (universal) as mental term

For Ockham, a universal is not a shared essence existing in things or a quality in the soul, but a mental term or concept that can signify many individual things.

Why essential: This concept is the linchpin of his solution to the problem of universals and connects directly to his theory of mental language and supposition.

Suppositio (supposition theory)

A semantic theory explaining how terms ‘stand for’ things in different contexts—personally (for individuals), simply (for concepts), or materially (for words)—thereby analyzing reference and truth conditions.

Why essential: Supposition theory is central to Ockham’s logic and his attempt to explain meaning and inference without positing real universals or species.

Lingua mentalis (mental language)

An internal, structured system of mental terms and propositions that naturally signify things and underlies all spoken and written languages.

Why essential: Mental language lets Ockham locate logical form and meaning in mental acts rather than in abstract entities, bridging his logic, metaphysics, and philosophy of mind.

Intuitiva cognitio and abstractive cognition

Intuitive cognition is direct awareness of an individual and its existence, while abstractive cognition considers an object’s nature or properties without determining whether it exists.

Why essential: This distinction is key to Ockham’s epistemology, his confidence in everyday knowledge of individuals, and his skepticism about demonstrative metaphysics and natural theology.

Potentia Dei absoluta / ordinata (absolute / ordained power of God)

The distinction between what God could do in principle as omnipotent (absolute power) and what God has in fact willed to do and bound Himself to in the existing order (ordained power).

Why essential: This framework shapes Ockham’s theology of contingency, his views on grace and salvation, and his account of how stable moral and legal norms can exist despite divine freedom.

Plenitudo potestatis and limits of papal authority

‘Fullness of power’ is the claim that the pope has supreme authority in the Church; Ockham contests expansive readings of this idea, arguing that papal power is ministerial, fallible, and bounded by Scripture and law.

Why essential: Understanding his critique of plenitudo potestatis is necessary to grasp his political writings, his break with John XXII, and his influence on conciliarism and ideas of limited government.

Common Misconceptions
Misconception 1

Ockham explicitly coined the exact phrase ‘entities must not be multiplied beyond necessity.’

Correction

The precise wording does not appear in his surviving works. Ockham articulates several principles of parsimony (e.g., ‘plurality is not to be posited without necessity’), and later tradition condensed these into the famous formula.

Source of confusion: Textbook summaries and popular accounts often treat the slogan as a verbatim quotation rather than a reconstruction of his methodological theme.

Misconception 2

Nominalism means Ockham denies any real similarities or stable order in the world.

Correction

Ockham denies real universal essences, but he accepts real individual similarities and patterns that our concepts track; he also retains a robust created order sustained by God’s will.

Source of confusion: Equating ‘no real universals’ with ‘no real structure’ overlooks his account of natural similarities and the role of mental language in representing them.

Misconception 3

Because Ockham stresses divine omnipotence and voluntarism, he makes morality completely arbitrary.

Correction

Ockham does hold many norms to be contingent on God’s free will, but he also affirms necessary precepts (like loving God) rooted in God’s nature and insists that God cannot will contradictions or evil as evil.

Source of confusion: Summaries of ‘divine command theory’ often oversimplify his nuanced distinction between necessary and contingent moral precepts.

Misconception 4

Ockham rejected the use of reason in theology and was a pure fideist.

Correction

He limits what natural reason can demonstratively prove (e.g., he denies strict proofs of God’s existence) but still uses logical analysis and philosophical argument extensively to clarify and defend revealed doctrines.

Source of confusion: His denial of certain traditional proofs and stress on scriptural authority can be mistaken for a blanket rejection of reason’s role.

Misconception 5

Ockham’s political thought is an early form of modern liberal secularism.

Correction

Ockham argues for limits on papal power and a distinction between spiritual and temporal authority, but he still grounds all legitimate power in God and operates within a medieval Christian framework.

Source of confusion: Later liberal and secular thinkers appropriated some of his arguments, leading to anachronistic readings of his intentions and conceptual framework.

Discussion Questions
Q1intermediate

How does Ockham’s nominalism about universals reshape traditional scholastic metaphysics, and what explanatory work does he think can still be done using only individuals and their qualities?

Hints: Compare his definition of universals as mental terms with realist accounts in Aquinas or Scotus; consider how he treats ens and res and what he does with haecceities and formal distinctions.

Q2advanced

In what ways does Ockham’s principle of parsimony (Ockham’s razor) operate differently in metaphysics, theology, and political theory?

Hints: Identify at least one example from each domain (e.g., rejection of real universals, caution about speculative eucharistic theories, critique of plenitudo potestatis) and analyze how ‘not positing without necessity’ is applied in each.

Q3intermediate

What is the role of intuitive and abstractive cognition in Ockham’s epistemology, and how does this distinction support both his confidence in everyday knowledge and his skepticism about demonstrative theology?

Hints: Explain what intuitive cognition tells us about existence and contingent features, how abstractive cognition underlies universal concepts, and why this still leaves many theological truths undemonstrable.

Q4advanced

How does Ockham’s distinction between God’s absolute and ordained power help him explain the contingency of the created order while preserving its reliability for human agents?

Hints: Contrast what God could do in absolute power with what God has in fact willed; consider implications for natural laws, moral norms, and the stability of promises about grace and salvation.

Q5advanced

To what extent does Ockham’s critique of papal plenitudo potestatis and his appeal to councils and the universitas fidelium anticipate later conciliarist and constitutional ideas?

Hints: Use examples from his Dialogus and political treatises; distinguish between his immediate aim (defending Franciscan poverty, resisting John XXII) and longer-term institutional implications.

Q6intermediate

In what ways does Ockham remain a typical scholastic thinker, and in what ways does he break with the ‘via antiqua’ tradition represented by Aquinas and Scotus?

Hints: Consider his use of Sentences commentaries, disputational method, and acceptance of core doctrines on the one hand, and his nominalism, epistemic limits, and political radicalism on the other.

Q7advanced

How should we assess the claim that Ockham is a precursor of modern empiricism and analytic philosophy of language?

Hints: Compare his emphasis on intuitive cognition and mental language with features of modern empiricism and analytic philosophy; discuss both similarities and important differences in aims and assumptions.