Perplexity report: Raul Corazzon’s Digital Quadrivium Project
Report date: January 30th, 2026
The Digital Quadrivium Project is a long‑term, single‑author, online research infrastructure created by Raul Corazzon that consists of four tightly connected, heavily annotated bibliographical websites on ontology, logic, rhetoric, and philosophy–religion broadly construed.
Overall structure and aims
The project unifies four sites:
Theory and History of Ontology (ontology.co)
History of Logic from Aristotle to Gödel (historyoflogic.com)
Theory and History of Rhetoric (historyofrhetoric.com)
All four share: a common search function, e‑book/PDF download options, a focus on historical development, and large, curated bibliographies with annotations and excerpts from primary and secondary literature.
Together they currently offer roughly 16800 references in ontology, 4300 in logic, 1300 in rhetoric, and 2400 in religion/philosophy, many with notes and abstracts, and they are explicitly described as works in progress with “thousands of new references” planned.
Raul Corazzon’s Digital Quadrivium Project is a unified, long‑term scholarly enterprise of four large, interlinked websites that provide deeply annotated bibliographies on ontology, logic, rhetoric, and philosophy of religion broadly understood.[1][2][3]
Together they offer around 26,800 bibliographic entries corresponding to about 13,700 PDF pages, with “thousands of new references” still being prepared.[3][1][2]
Each site can be downloaded as an ebook/PDF and all share a cross‑site search, so the four function as one integrated resource.[1][2][3]
Scope by site (pages in PDF format)
Site
Thematic focus
Approx. references
Approx. PDF pages
Theory and History of Ontology
Ontology, metaphysics, related history of philosophy
(All totals are explicitly stated by Corazzon on the sites.)[2][3][1]
Theory and History of Ontology
Aims and intellectual profile
Corazzon defines ontology as “the theory of objects and their ties,” distinguishing concrete/abstract, existent/nonexistent, real/ideal, independent/dependent objects and their relations.[1]
He distinguishes three kinds of ontology: (a) formal, (b) descriptive, and (c) formalized ontology.[1]
Formal ontology, following Husserl, studies the “genera of being” and fundamental categories using eidetic reduction and categorial intuition.[1]
Historical lineages: from Bolzano, Brentano, Meinong, Husserl, Frege and Twardowski to twentieth‑century phenomenological, analytic, Austro‑Polish and so‑called “Continental” ontologies (Heidegger, Merleau‑Ponty, Levinas, Deleuze, Foucault, etc.).[1]
Conceptual analyses:
Formal vs material ontology (Husserl and Albertazzi).[1]
Theory of objects (Meinong, Twardowski, Ingarden, Farber).[1]
Logic and ontology (Bochenski, Cocchiarella) and the relation to Leibniz’s characteristica universalis and calculus ratiocinator.[1]
Definitions from analytic metaphysics and ontology: quotations and commentary from Dejnožka, Jacquette, Simons, Cameron and others on different senses of “ontology” and its relation to metaphysics.[1]
Special features
“Table of Ontologists of 19th and 20th Centuries” tracing lines from Bolzano–Brentano–Frege to contemporary authors, with entries including bibliographies, abstracts, and critical judgments.[1]
Extensive, language‑diverse bibliographies: about 16,800 references in English, French, German, Italian, Spanish, and Portuguese, focusing on under‑documented ontological topics and authors.[1]
Systematic attention to interfaces with logic, semantics, and semiotics, especially predication, reference, and the relation between thought, language, and world.[1]
History of Logic from Aristotle to Gödel
Aims and coverage
Dedicated to the history of logic, especially formal logic, “from Aristotle to Gödel.”[2][1]
Uses as a conceptual starting point Joseph Bochenski’s A History of Formal Logic and his article “Logic and Ontology,” both heavily excerpted and annotated.[2][1]
Conceptual framework (following Bochenski)
Logic is delimited historically by reference to Aristotle’s Organon, especially the Prior Analytics and its theory of syllogism and logical form.[2][1]
Bochenski distinguishes several questions about relations between logic and ontology: objective content, subjective (historical) views, and metatheoretical philosophies of logic.[2][1]
He reconstructs historical positions from Aristotle, the Stoics, Scholastics, Humanists, Leibniz, and the era up to Boole, emphasizing shifts between logic as dialectical art, metalinguistic rules, and formal systems.[2][1]
Logical history emphasis
The site’s materials (through long quotations and bibliographic notes) stress:[2][1]
Aristotle’s dual legacy:
An ontology of “being as being” with categorial analyses;
Two logics: topical (dialectical) and formal syllogistic, with incomplete meta‑logical reflection.[2][1]
Stoic innovations: a propositional logic and a clear conception of logic as a rule‑system operating on ideal meanings distinct from real bodies.[2][1]
Scholastic logic: a metalinguistic, rule‑oriented discipline dealing with propositions and “second intentions,” sharply distinguished from ontology but overlapping it (e.g., two versions of non‑contradiction).[2][1]
Early modern “conventional logic”: psychologism, the reduction of logic to a practical “art of thinking,” and the marginalization of formal logic except in Leibniz.[2][1]
The revival of historical research on ancient logic in the late nineteenth and twentieth centuries (Peirce, Vailati, Rüstow, Łukasiewicz, Scholz, Mates, Ross, etc.).[2][1]
Bibliographic profile
The site aggregates about 4,300 annotated references on logic’s history, especially Aristotelian, Stoic, medieval, and early modern traditions, plus early developments of modern formal logic.[3][2][1]
Annotations often highlight how each work treats the relation between logic, metaphysics, and ontology, consistent with the project’s cross‑site theme.[2][1]
Theory and History of Rhetoric
Aims and conceptual framing
Focused on the historical development of rhetoric, conceived in close relation to dialectic and logic.[3]
Corazzon cites Aristotle’s definition of rhetoric as antistrophos (counterpart) of dialectic and as “a sort of offshoot of dialectic and of work in ethics, which it is right to call politics,” and Heidegger’s claim that rhetoric is a “first part of logic rightly understood.”[3]
Planned and current content
The site is structured around large bibliographic sections:[3]
General works: theory of rhetoric, argumentation theory, rhetoric and philosophy, critical thinking, feminist rhetoric, and bibliographies of dictionaries and encyclopedias of rhetoric.[3]
History of rhetoric:
Greek rhetoric (from early sophists to Hellenistic and later Peripatetics, with sections on Protagoras, Gorgias, Isocrates, Plato, Aristotle, Attic orators, Stoics, and other schools).[3]
Roman rhetoric (Cato, Cicero, Augustan rhetoric, Second Sophistic, Christian rhetoric).[3]
Medieval rhetoric (Augustine, ars poetriae, ars dictaminis, ars predicandi).[3]
Renaissance and early modern rhetoric (Valla, Vives, Agricola, Erasmus, Melanchthon, Ramus, Keckermann, Vico, Campbell, Priestly, Lamy, Fénélon, Adam Smith, Hugh Blair).[3]
Comparative rhetoric: overviews and region‑specific bibliographies for African, African‑American, Pre‑Columbian American, Ancient Egyptian, Jewish, Arabic, Syriac, Celtic, Near Eastern, Asian, Chinese, and Japanese traditions.[3]
Vocabulary of rhetoric: key notions such as enthymeme, epideictic, ethos, logos, pathos, and pisteis.[3]
Stage of development
Corazzon notes that this site is still in an early stage: only a subset of planned sections is online, but more pages will be added.[3]
Even at this stage it encompasses roughly 1,300 references, corresponding to around 600 PDF pages.[3]
Bibliographia. Annotated Bibliographies on Philosophy and Religion
Aims and thematic focus
Dedicated to bibliographical resources on philosophy and religion, with initial focus on the history of early Christianity.[1]
It complements co and historyoflogic.com by covering topics in philosophy of religion, phenomenology of religion, sociology of religion, and major religious traditions beyond Christianity and Judaism.[1]
Bibliographies of philosophy: topics in philosophy not treated extensively on the other sites.[1]
Hebrew Bible: formation of the Pentateuch and canon, pseudepigrapha, textual criticism, and the history of research.[1]
New Testament: synoptic question, individual gospels, letters, Acts, Revelation, canon formation, pseudepigrapha, textual criticism, and history of research.[1]
Literature of Early Christianity: Apostolic Fathers, orthodoxy and heresy.[1]
Literature of Early Judaism: birth of Judaism, “parting of the ways” between Christianity and Judaism.[1]
Philosophy and phenomenology of religion: definitions of religion, analytic vs continental approaches, sacred/profane, debates on the existence of God.[1]
Sociology of religion: sociological studies of early Christianity, charisma and routinization, messianism and millenarianism.[1]
Study guides: bibliographies of dictionaries and encyclopedias of philosophy, style manuals for philosophy students, and introductory readings on the history of philosophy, metaphysics, ontology, and philosophy of logic.[1]
Other religions: planned bibliographies on major non‑Jewish, non‑Christian religions.[1]
Stage and volume
Like the rhetoric site, Bibliographia is described as being in an early stage, with only some sections currently available but more planned.[1]
It already accounts for about 2,400 bibliographic entries, about 1,500 PDF pages.[1]
Unifying features of the Digital Quadrivium Project
Conceptual unity
The project’s title “Digital Quadrivium” alludes to a modern analogue of the medieval quadrivium: instead of arithmetic, geometry, music, and astronomy, Corazzon’s four pillars are ontology, logic, rhetoric, and broad philosophical–religious bibliography.[2][3][1]
Across the sites, he repeatedly emphasizes the interrelation of ontology and logic (formal and material ontology, theory of objects, categorial analysis) and the close connection of rhetoric with dialectic, ethics, politics, and logic.[3][2][1]
Strong historical orientation, from classical sources (Aristotle, Stoics) through medieval and early modern thinkers to contemporary authors.
Heavy use of primary and secondary literature excerpts, with careful crediting and notes, but the sites’ distinctive value lies in their structured, themed, and often annotated bibliographies.
Emphasis on under‑covered topics and authors, and on non‑English‑language scholarship (notably Italian, German, French, Spanish, Portuguese).
Shared infrastructure: identical banner identifying them as parts of a single project, cross‑site search, regular update notes (e.g., January 19, 2026 for ontology and rhetoric, December 16, 2025 for history of logic, October 15, 2025 for Bibliographia).[3][2][1]
Use‑cases for researchers
Ontology & metaphysics: comprehensive starting point for work on Husserlian formal ontology, analytic metaphysics, Meinongian object theory, Austro‑Polish ontology, and the Continental tradition.[1]
Logic: historically informed research on Aristotelian syllogistic, Stoic propositional logic, medieval metalinguistic logic, and early modern developments, with an eye to their philosophical interpretations.[2][1]
Rhetoric & argumentation: cross‑disciplinary work linking classical rhetoric, argumentation theory, and contemporary critical thinking or feminist rhetoric, including non‑Western traditions.[3]
Religion & philosophy: projects on early Christianity and Judaism, philosophy and phenomenology of religion, and sociology of religion, supported by dense, topic‑specific bibliographies.[4]
If you want, I can next:
Map concrete research strategies (e.g., “how to use these four sites to build a literature review on formal ontology and its relation to logic”), or extract and organize key ontological/logical/rhetorical schools and authors into a working reading plan.
