The Architecture Of The Summa Theologica: A Reader’s Guide To The Masterwork Of Thomas Aquinas

Posted on by Brian Colwell

Opening the Summa Theologica for the first time can feel like entering a vast Gothic cathedral. The sheer scale is overwhelming—nearly 3,000 pages in most editions, containing 512 questions subdivided into 2,669 articles.

The formal scholastic method, with its objections and replies, seems foreign to modern readers accustomed to narrative prose. Yet like a cathedral, the Summa has a magnificent architecture that, once understood, reveals both its beauty and its practical purpose.

This guide will help you navigate Aquinas’s masterwork, understanding not just its structure but the genius behind its design.

Additional Resources For Your Research

Summa Theologica Table Of Contents – Quicklinks

A Treatise On God: Questions 1-26 Of The First Part Of The Summa Theologica

The Architecture Of The Summa Theologica

To appreciate the Summa’s architecture, we need to understand why Aquinas wrote it. By the 1260s, theology education in Paris was in crisis. Students were overwhelmed by competing authorities, confused by poorly organized textbooks, and lost in endless disputations without clear resolution. The standard theological textbook, Peter Lombard’s Sentences, was becoming increasingly unwieldy as masters added layer upon layer of commentary.

Aquinas, drawing on his experience teaching in Paris and Italy, recognized the need for a comprehensive yet accessible theological textbook. The Summa Theologica (Summary of Theology) was his response—intended, as he states in the prologue, for “beginners” in theology. This might surprise modern readers who find it challenging, but Aquinas meant students who already had training in philosophy and scripture but were beginning their formal theological studies.

Three Parts Mirroring Reality

The Summa’s most striking feature is its tripartite structure, which embodies a theological vision and mirrors the Neo-Platonic understanding of reality as exodus and return: all things come from God (Part I), and all things—especially rational creatures—are called to return to God (Part II) through Christ (Part III). The structure itself teaches that theology isn’t merely about God – but about God as the origin and destiny of all things.

Part I (Prima Pars): God and the procession of creatures from God

  • Questions 1-119 focus on God in Himself and as Creator
  • Covers the divine nature, Trinity, creation, angels, and human nature

Part II (Secunda Pars): The movement of rational creatures back to God

  • Divided into two sections:
    • I-II (Prima Secundae): General moral theology—human acts, passions, habits, virtues, law, and grace
    • II-II (Secunda Secundae): Particular virtues and vices, states of life

Part III (Tertia Pars): Christ, who as man is our way to God

  • Questions 1-90 cover Christology and sacraments
  • Left unfinished at Aquinas’s death in 1274
  • Completed with a supplement drawn from his earlier works

The Micro-Architecture: The Disputed Question Format

Each article within the Summa follows a rigorous format derived from medieval university disputations. This format isn’t arbitrary. It embodies the scholastic conviction that truth emerges through rigorous dialectical engagement with opposing views. By starting with objections, Aquinas shows respect for contrary positions and demonstrates that he understands them before refuting them. This method teaches intellectual humility and thoroughness.

Aquinas utilizes the following disputed question format throughout his Summa Theologica:

The Question (Utrum…): “Whether…” – A specific yes/no question is posed

Objections (Videtur quod…): “It seems that…” – Typically 3-4 arguments against Aquinas’s position

Sed Contra: “On the contrary…” – A brief authoritative statement supporting his position

Respondeo (I answer that…): Aquinas’s main argument

Replies to Objections: Specific responses to each opening objection

Why Aquinas Starts With Sacred Doctrine

The placement of Question 1 on sacred doctrine is architecturally crucial. Before discussing God, creation, or morality, Aquinas establishes his method and foundations. This opening question addresses:

  • Why revealed theology is necessary alongside philosophy
  • How theology can be a science
  • The relationship between faith and reason
  • How to interpret Scripture
  • The use of metaphorical language in theology

Starting here is genius for several reasons. First, it prevents misunderstandings about what kind of work the Summa is—it’s theology, not pure philosophy, though it uses philosophical methods. Second, it establishes that human reason, while valuable, needs divine revelation to reach its supernatural end. Third, it sets up the harmony between faith and reason that characterizes the entire work.

Modern readers often skip this question, eager to get to “the good stuff” about God’s existence or human nature. This is a mistake. Question 1 provides the hermeneutical key to everything that follows. Without understanding Aquinas’s view of theological method, readers will misinterpret his arguments as purely philosophical when they’re actually theological arguments using philosophical tools.

The Progressive Pedagogy

The Summa’s order isn’t arbitrary but pedagogical. Aquinas carefully structures the work so that each section builds on previous conclusions. Each question presupposes and builds on earlier conclusions. This progressive structure means the Summa is best read sequentially, at least within major sections. Jumping to isolated questions risks misunderstanding, as Aquinas often assumes familiarity with earlier established principles.

For example, one can’t properly understand divine simplicity (Q3), without first establishing God’s existence (Q2), and can’t grasp how we name God (Q13) without understanding His simplicity and perfection. Consider the opening of Part I:

  • Q1: Establishes that we can speak meaningfully about God through revelation
  • Q2: Proves God exists (the Five Ways)
  • Q3-11: Explores God’s attributes via negation (simplicity, perfection, goodness, infinity, etc.)
  • Q12-13: Discusses how we can know and name God
  • Q14-26: Examines God’s operations (knowledge, will, power)

Reading The Summa Theologica

The Summa Theologica is not a book to be mastered but a cathedral to be explored. Its architecture guides us from the foundations of theological method through the heights of divine mystery to the practical matters of human life and destiny. Like any great building, it rewards repeated visits. Each reading reveals new connections, deeper insights, and forgotten chambers.

The key is to begin. Choose a section, read slowly, and let Aquinas’s careful method shape your thinking. Don’t be discouraged by initial difficulties—medieval students spent years studying the Summa. But also don’t be intimidated. Aquinas wrote for beginners, and his clarity of thought, once you adjust to his method, is remarkable.

Reading Strategies

  • Master the method: Learn to identify the structure of each article. Practice distinguishing objections from Aquinas’s own position. Many misreadings come from taking objections as Aquinas’s views.
  • Keep a philosophical dictionary handy: Terms like “substance,” “accident,” “form,” “matter,” “act,” and “potency” have technical meanings. Misunderstanding these terms will lead to misunderstanding arguments.
  • Read actively: Try to formulate Aquinas’s arguments in your own words. Can you explain why he structures the argument as he does? Why does he consider those particular objections?
  • Pay attention to authorities: Aquinas quotes Scripture, Aristotle (“the Philosopher”), Augustine, Pseudo-Dionysius, and others. Understanding his use of authorities helps grasp his method of combining faith and reason.

Common Pitfalls To Avoid

  • Don’t rush: The Summa rewards slow, careful reading. Better to thoroughly understand a few questions than to skim many superficially.
  • Don’t mistake objections for Aquinas’s positions: The initial “It seems that…” sections present views Aquinas will refute. Many critics of Aquinas actually attack positions he explicitly rejects.
  • Don’t read with modern philosophical assumptions: Aquinas operates within a different metaphysical framework. Terms like “cause,” “being,” and “good” don’t always mean what modern philosophy assumes.
  • Don’t isolate philosophy from theology: The Summa is a theological work. Even apparently purely philosophical sections serve theological purposes.
  • Don’t expect modern literary style: The Summa prioritizes clarity and precision over eloquence. Its beauty lies in its logical architecture, not rhetorical flourishes.

Why Read The Summa Theologica Today?

In our age of tweets and hot takes, the Summa’s measured method offers a counter-cultural witness. It teaches us to:

  • Consider opposing views carefully before responding
  • Build arguments systematically on solid foundations
  • Integrate faith and reason rather than opposing them
  • Pursue truth patiently rather than rhetorical victory

The Summa’s architecture embodies a vision of reality as intelligible, ordered, and ultimately grounded in God. Its method assumes that patient, careful thinking can lead us closer to truth. In a fragmented age, it offers an integrated vision of God, humanity, and the cosmos.

Final Thoughts

As you read, remember that for Aquinas, theology was not merely an academic exercise but a spiritual discipline. He began each writing session with prayer, seeking not just to understand divine truths but to be transformed by them. The Summa’s architecture ultimately serves this purpose: to lead us through understanding to love, through careful distinctions to simple contemplation, through many words to the Word Himself.

Thanks for reading!