Summa Theologica Thomas Aquinas

The Summa is structured into:

• 3 Parts ("Pt."), subdivided into:
  • 614 Questions (quaestiones; or "QQ"), subdivided into:
    • 3,125 Articles ("Art.").

Questions are specific topics of discussion, whereas their corresponding Articles are further-specified facets of the parent question. For example, Part I, Question 2 ("The Existence of God") is divided into three articles: (1) "Whether the existence of God is self-evident?"; (2) "Whether it can be demonstrated that God exists?"; and (3) "Whether God exists?" Additionally, questions on a broader theme are grouped into Treatises, though the category of treatise is reported differently, depending on the source.

The Summa's three parts have a few other major subdivisions.

• First Part (Prima Pars; includes 119 QQ, 584 Articles): The existence and nature of God; the creation of the world; angels; and the nature of man.
• Second Part (includes 303 QQ, 1536 Articles), subdivided into two sub-parts:

• First part of the Second Part (Prima Secundae or Part I-II; includes 114 QQ, 619 Articles): General principles of morality (including a theory of law).
• Second part of the Second Part (Secunda Secundae or Part II-II; includes 189 QQ, 917 Articles): Morality in particular, including individual virtues and vices.

• Third Part (Tertia Pars; includes 90 QQ, 549 Articles): The person and work of Christ, who is the way of man to God; and the sacraments. Aquinas left this part unfinished.[6]

• Supplement (99 QQ, 446 Articles): The third part proper is attended by a posthumous supplement which concludes the third part and the Summa, treating of Christian eschatology, or "the last things".

• Appendix I (includes 2 QQ, 8 Articles) and Appendix II (includes 1 Q, 2 Articles): Two very small appendices which discuss the subject of purgatory.

Article format

The method of exposition undertaken in the articles of the Summa is derived from Averroes, to whom Aquinas refers respectfully as "the Commentator".[7] The standard format for articles of the Summa is as follows:

1. A series of objections (praeterea) to the yet-to-be-stated conclusion are given. This conclusion can mostly (but not without exception) be extracted by setting the introduction to the first objection into the negative.
2. A short counter-statement is given, beginning with the phrase sed contra ('on the contrary...'). This statement almost always references authoritative literature, such as the Bible, Aristotle, or the Church Fathers.[8]
3. The actual argument is made, beginning with the phrase respondeo dicendum quod ('I answer that...'). This is generally a clarification of the issue.
4. Individual replies to the preceding objections or the counter-statement are given, if necessary. These replies range from one sentence to several paragraphs in length.

Example

Consider the example of Part III, Question 40 ("Of Christ's Manner of Life"),[i] Article 3 ("Whether Christ should have led a life of poverty in this world?"):[ii]

1. First, a series of objections to the conclusion are provided, followed by the extracted conclusion ('therefore'):
   • Objection 1: "Christ should have embraced the most eligible form of life...which is a mean between riches and poverty.... Therefore Christ should have led a life, not of poverty, but of moderation."
   • Objection 2: "Christ conformed His manner of life to those among whom He lived, in the matter of food and raiment. Therefore, it seems that He should have observed the ordinary manner of life as to riches and poverty, and have avoided extreme poverty."
   • Objection 3: "Christ specially invited men to imitate His example of humility.... But humility is most commendable in the rich.... Therefore it seems that Christ should not have chosen a life of poverty."
2. A counter-statement is given by referring to Matthew 8:20 and Matthew 17:26.
3. The actual argument is made: "it was fitting for Christ to lead a life of poverty in this world" for four distinct reasons. The article then expounds on these reasons in detail.
4. Aquinas' reply to the above objection is that "those who wish to live virtuously need to avoid abundance of riches and beggary...but voluntary poverty is not open to this danger: and such was the poverty chosen by Christ."

Structure of Part II

Part II of the Summa is divided into two parts (Prima Secundae and Secunda Secundae, cited respectively as "1a2æ" and "2a2æ"). The first part comprises 114 questions, while the second part comprises 189. The two parts of the second part are usually presented as containing several "treatises". The contents are as follows:[9]

Part II-I

• Treatise on the last end (qq. 1–5):[iii]
• Treatise on human acts (qq. 6–21)[iv]
  • The will in general (qq. 6–7)
  • The Will (qq. 8–17)
  • Good and evil (qq. 8–21)
• Treatise on passions (qq. 22–48)[v]
  • Passions in general (qq. 22–25)
  • Love and hatred (qq. 26–29)
  • Concupiscence and delight (qq. 30–34)
  • Pain and sorrow (qq. 35–39)
  • Fear and daring (qq. 40–45)
  • Anger (qq. 46–48)
• Treatise on habits (qq. 49–70)[vi]
  • Habits in general; their causes and effects (qq. 49–54)
  • Virtues; intellectual and moral virtues (qq. 55–60)
  • Virtues; cardinal and theological virtues (qq. 61–67)
  • The gifts, beatitudes and blessings of the Holy Ghost (qq. 68–70)
• Treatise on vice and sin (qq. 71–89)[vii]
  • Vice and sin in themselves; the comparison of sins (qq. 71–74)
  • The general causes of sin; the internal causes of sin (qq. 75–78)
  • The external causes of sin, such as the devil and man himself (qq. 79–84)
  • The corruption of nature the stain of sin; punishment for venial and mortal sin (qq. 85–89)
• Treatise on law (qq. 90–108)[viii]
  • The essence of law; the various kinds of law; its effects (qq. 90–92)
  • Eternal law, natural law, human law (qq. 93–97)
  • The old law; ceremonial and judicial precepts (qq. 98–105)
  • The law of the Gospel or new law (qq. 106–108)
• Treatise on grace (qq. 109–114): its necessity, essence, cause and effects[ix]

Part II-II

• Treatise on the theological virtues (qq. 1–46)
• Treatise on the cardinal virtues (qq. 47–170)
  • Treatise on prudence (qq. 47–56)
  • Treatise on justice (qq. 57–122)
  • Treatise on fortitude and temperance (qq. 123–170)
• Treatise on gratuitous graces (qq. 171–182)
• Treatise on the states of life (qq. 183–189)