- Length
- 3020 pagesThe Blackfriars edition, 61 vols, Latin with facing English, 1964-81
- Reading
- DemandingReadable with attention; assumes no other book
- Availability
- Many editionsIn print in several competing editions
Summa Theologiae
The largest and most orderly philosophical work of the Middle Ages, written as an introduction, abandoned unfinished when its author stopped writing altogether, and condemned within three years of his death before becoming the official philosophy of the Catholic Church.
- Date
- 1265-1274
- Author
- Thomas Aquinas
- Region
- Rome, Paris and Naples
- Language
- Latin
- 1911 English, the English Dominican Province Public domain; the basis of most online texts Attested
- 1964 English, the Blackfriars edition 61 volumes, Latin with facing English; in copyright Attested
Where it stands in the argument
- Position
- Exchange — Both: answers an earlier work and drew a later one
- Form
- Treatise
- Method
- Dialectical — Advance through contradiction and its resolution
- Transmission
- Continuous — Copied and read without a break in its own language
- Standing
- Live — Still argued in current philosophical work
- Years to the reply
- 26 years
- Years back to what it answers
- 196 years
Condemned in part at Paris and Oxford within three years of Aquinas' death, and made the required text of Catholic theology six centuries later.
What the book says
A textbook for beginners that runs to about two and a half million words and was never finished. Every one of its five hundred-odd questions has the same shape, and the shape is the method: the question is put, several objections to the answer Aquinas will give are stated as strongly as he can state them, a contrary authority is cited, his own determination follows, and then each objection is answered individually. Nothing is asserted before the case against it has been made. The first part treats God and creation, and opens with the five ways of arguing to God's existence from motion, causation, contingency, degrees of perfection and the ordering of things - all of them starting from the world, none of them from the concept. The second part, by far the longest, is on human action: happiness, the passions, the virtues, law in its several kinds, and grace. The third turns to Christ and the sacraments and stops. Throughout, Aristotle is called simply the Philosopher and Ibn Rushd the Commentator, and Ibn Sina, Maimonides and the Fathers are argued with by name on almost every page.
What it argues
That reason and revelation cannot conflict because both come from the same source, and that a great deal about God, the soul and the good can be established by reason alone. The five ways are the display case: each begins from something anyone can observe - that things move, that there are causes, that things come and go, that things are more or less good, that unthinking things behave regularly - and argues to a terminus. On human action Aquinas takes over the Aristotelian account of virtue and happiness and extends it, arguing that the natural end of a human being is knowable by reason while the final end exceeds it. The account of law is the part with the longest afterlife: eternal, natural, human and divine, with natural law accessible to anyone and human law binding only as it conforms to it.
What it answered
Proslogion 1078Anselm of Canterbury
Anselm on the question of proof, and the whole prior Latin tradition on method. The wider answer is to the arrival of Aristotle. The complete Aristotle had reached the universities within Aquinas' lifetime, in Arabic-influenced translations with Ibn Rushd's commentaries attached, and it carried doctrines - the eternity of the world, a single shared intellect - that could not be reconciled with Christian teaching. The response of the previous generation had been to restrict him. Aquinas' was to absorb him, arguing point by point which conclusions the arguments actually support.
What answered it
Ordinatio c. 1300-1304John Duns Scotus
Scotus first, and then Ockham. Scotus' attack on analogy and his doctrine of univocal being were aimed at the foundations of Thomist natural theology; Ockham's razor and his nominalism went further, dismantling the metaphysical apparatus both had assumed. The Church answered too: in 1277 the bishop of Paris condemned two hundred and nineteen propositions, some of them Thomist, and Oxford followed. The reversal took time and was complete by 1323, when Aquinas was canonised, and in 1879 an encyclical made his philosophy the required framework of Catholic teaching.
How it argues
In the question form Abelard's method had generated and Peter Lombard's textbook had standardised, applied with more discipline than anyone before or since. The objections are stated well enough that the Summa functions as an anthology of the positions it rejects, and the replies address each objection separately rather than collectively. The effect of that structure is that the book cannot be read as a system being expounded; it is a system being interrogated, article by article, and the interrogation is what a reader is meant to learn.
The moment
The thirteenth-century universities, with a new religious order sending its ablest men into them and the Aristotelian corpus arriving faster than it could be assimilated. Aquinas was a Dominican, taught at Paris and Naples, and worked at extraordinary speed with several secretaries. On 6 December 1273 something happened during Mass after which he stopped writing; asked why, he is reported to have said that what he had written seemed like straw. He died three months later, aged about forty-nine.
How it travelled
Continuously, and with a career unlike any other book here. Condemned in part in 1277, defended by his order, canonised with his author in 1323, made a set text at the Council of Trent, and installed by papal instruction in 1879 as the philosophy of the Church - which produced a revival of scholarship that has continued past the point where the institutional requirement was relaxed. The critical Leonine edition, begun in 1882, is still not complete.
The strongest objection
Scotus', because it goes underneath rather than at. Aquinas needs being to be said of God and creatures analogically - not the same sense, not simply different senses - because univocity would make God one more item in a category and equivocity would make the arguments from the world invalid. Scotus' charge is that analogy cannot be a third thing: either the middle term of an argument means the same in both premises or the argument equivocates, and if there is no concept common to God and creatures then the five ways prove something about the world and stop there. The Thomist reply, that analogy is a genuine third case, is exactly what is at issue, and the dispute has never been settled.
Why read it
Never entire - it was designed as a reference work and functions as one. The first question, on whether theology is needed at all; the second, on God's existence; the treatise on law in the second part; and the questions on happiness are each self-contained and are among the clearest philosophical prose ever written. The article structure means any question can be read alone.
- First printed
- 1463
- First in English
- 1911
- Digitised
- Yes
The Leonine edition, begun in 1882 on papal instruction, is the critical text and is still not complete. The supplement to the third part was assembled after Aquinas' death from his commentary on the Sentences and is not his own composition.
The English Dominican Province translation of 1911-25 is public domain and is what most online versions use. The Blackfriars edition of 1964-81 and the modern versions are in copyright.
Where it stands
Live, and not only confessionally. Natural law theory is a live position in jurisprudence and ethics, analytic philosophers of religion work on the five ways and on divine simplicity, and the virtue-ethics revival brought the second part back into general use. Anyone arguing about the doctrine of double effect is using this book.
On quoting this book
The Latin is public domain and the 1911-25 English is too, but that version's technical vocabulary is now regarded as misleading in several places. Nothing is quoted.
Contested
What happened on 6 December 1273 is unknown and has been variously described as a mystical experience, a stroke and exhaustion. How much of the third part's supplement represents Aquinas' settled view is uncertain, since he did not write it. Whether the Aristotelianism is a genuine synthesis or a Christian framework with Aristotelian furniture is argued. And which of the 1277 condemnations were actually aimed at Aquinas rather than at the radical Aristotelians is a long-running historical question with no agreed answer.