The Summa Contra Gentiles is Aquinas's earlier systematic theology — in four books, addressed to readers who do not share Christian scriptural premises and proceeding from arguments accessible to natural reason.
summa-contra-gentiles
Aquinas's earlier and more apologetic Summa, in four books, addressing Christian doctrine to readers (Muslims, Jews, pagans) who do not share its scriptural premises.
Composed 1259–1265.
Introduction
The Summa Contra Gentiles (literally Summa Against the Gentiles) is Thomas Aquinas's earlier systematic theology, composed between 1259 and 1265. Where the Summa Theologiae is a textbook for Christian students and presupposes scriptural premises throughout, the Summa Contra Gentiles is apologetic in orientation: it addresses readers who do not share Christian premises and proceeds, where possible, from arguments accessible to natural reason alone.
The work is structured in four books rather than the three of the later Summa. It is also stylistically distinct, written in continuous prose rather than the quaestio format. The two Summae together constitute Aquinas's complete systematic project; each addresses a different audience and uses a different method.
Form, length, date, language
The Summa Contra Gentiles is a treatise in four books, totaling approximately 280,000 words in Latin. Books I–III treat the philosophical theology accessible (in principle) to natural reason; Book IV treats the doctrines available only through revelation. The work was composed between 1259 and 1265, during Aquinas's first Italian period after his initial Parisian regency. The original language is medieval scholastic Latin.
The traditional account of the work's occasion comes from the early Dominican chronicler Peter Marsilius (writing around 1313): the Summa Contra Gentiles was composed at the request of Raymond of Peñafort, then master general of the Dominicans, for use by Dominican missionaries in Spain working among Muslims and Jews. This account is now widely doubted by scholars; the internal evidence suggests an academic audience rather than a missionary one. The work is probably better understood as a philosophical-theological treatise aimed at an educated readership not necessarily sharing all Christian premises.
Why it was written
The organizing methodological choice of the Contra Gentiles is the distinction between truths accessible to natural reason and truths available only through divine revelation. Aquinas argues in Book I.3 that both kinds of truth exist: some doctrines about God (his existence, certain attributes) can be established philosophically; others (the Trinity, the Incarnation) cannot be established without revelation.
The argumentative strategy follows from this distinction. In the first three books, Aquinas argues from premises (in principle) accessible to any rational person, including non-Christians. The arguments draw heavily on Aristotelian and Neoplatonist materials, on Islamic philosophers (especially Avicenna and Averroes), and on Jewish philosophers (especially Maimonides). Only in Book IV does Aquinas argue from explicitly scriptural and revealed premises, addressing the doctrines that require revelation to be known.
The project is therefore both philosophical and apologetic. Philosophically, it demonstrates how far natural reason can go in establishing theological truths. Apologetically, it shows that the Christian position can be defended without circularity — the foundational doctrines can be argued for on grounds the opponent accepts.
Structure and argument
Book I: God. The existence of God; the divine attributes (simplicity, perfection, goodness, infinity, eternity, unity); the divine intellect and will. The arguments parallel those of the later Summa Theologiae Ia but are developed in continuous prose rather than disputational format. The Five Ways for God's existence appear in essentially the same form (though spread across Book I).
Book II: Creation. The creation of the world ex nihilo; the distinction between creator and creature; the angels; the human soul. The book includes Aquinas's extensive engagement with the Averroist doctrine of a single shared intellect for all humans — the position that Aquinas treats as one of the most important philosophical errors to refute.
Book III: Providence. The relation between God and creatures; divine providence and human freedom; happiness as the human end; the goods and evils of human life; the conditions of human flourishing. The treatment of happiness in Book III is the philosophical anticipation of the more theological treatment in the Summa Theologiae Ia-IIae.
Book IV: Revealed doctrines. Trinity, Incarnation, sacraments, eschatology. The arguments here are explicitly drawn from scriptural and traditional Christian sources; the natural-reason mode of the previous books gives way to theological argument proper.
Key passages
- I.1–9 — the methodological introduction; the distinction between natural and revealed truth.
- I.13 — the demonstration of God's existence.
- I.22 — the doctrine of analogy (essence and existence in God).
- II.59–78 — the extended refutation of Averroist monopsychism.
- III.16–63 — the analysis of happiness as the human end and the conditions of its attainment.
- III.111–163 — the doctrine of divine providence and human freedom.
- IV.1–49 — the doctrine of the Trinity, Incarnation, and the work of Christ.
Reception history
The Summa Contra Gentiles was respected throughout the medieval and early modern period as a major work of Christian philosophical theology, though it was generally less read than the Summa Theologiae (which served the standard pedagogical purpose). It was significant in the Renaissance debates about the relation between Christian philosophy and pagan thought, and in early modern dialogue between Christianity and other religious traditions.
The nineteenth-century Catholic recovery of Aquinas (the Neo-Thomist movement) often returned to the Contra Gentiles as the more philosophical of the two Summae and as a model for natural theology accessible to non-Christian readers. Étienne Gilson's The Christian Philosophy of St. Thomas Aquinas (1956) drew extensively on it.
The contemporary reception has been more substantial than the Contra Gentiles's general reputation suggests. The book's methodological commitment — arguing from premises accessible to a non-Christian interlocutor — makes it particularly useful for contemporary interreligious dialogue and for analytic philosophy of religion. The arguments against the Averroist single-intellect doctrine in Book II remain one of the most-engaged sections.
Contemporary engagement
The standard Latin edition is the Leonine Editio Leonina. The standard English translation is the five-volume Notre Dame translation (Pegis, Anderson, Bourke, O'Neil, 1955–1957), available online. Major recent scholarly work includes the relevant chapters in the Cambridge Companion to Aquinas (Davies and Stump), Norman Kretzmann's three-volume project (The Metaphysics of Theism, 1997; The Metaphysics of Creation, 1999; The Metaphysics of God Incarnate, unfinished at his death) which proceeds book-by-book through the Contra Gentiles, and Brian Davies's Aquinas (2002). Active scholarly disputes concern the actual historical occasion of the work, the relation between the Contra Gentiles and the Summa Theologiae, and the contemporary applicability of the natural-reason methodology to interreligious and secular dialogue.
Further reading
- Aquinas — the author
- Summa Theologiae — the companion later work
- Scholasticism — the tradition
- Christian Theology — the tradition
- Aristotelianism — the philosophical framework
- Aristotle — the foundational philosophical authority
Aquinas's earlier, more philosophically apologetic Summa. The model for Christian engagement with non-Christian philosophical interlocutors.