[4.9.13] St Thomas Aquinas on Virtues

St Thomas Aquinas (1225 – 1274 AD), in different works ([ST] Summa Theologiae and Quaestiones Disputatae de Veritate) lays out his theory of virtues. Based on that:

  • A human’s practical reason (see [1.3.6], [4.9.9]) is responsible for deliberating and freely choosing choices for the human good (or bad).
  • Practical reason uses first principles (e.g., “Good is to be done and pursued, and bad avoided”) aimed at the human good in the deliberation over the acts.
  • virtue is an element in a person’s (good) character.
  • Virtue means a stable willingness to make good choices.

Aquinas’s main model of virtues is pictured in the following OntoUML diagram:

Aquinas on virtues
HumanPersona human person
Character“A virtue is an aspect of, or constitutive element in, being a person of good character.”characterizes HumanPerson
PracticalReasonPractical reason’s central activity is deliberation about what to do. One would have no need to deliberate unless one were confronted by alternative attractive possibilities for action (kinds of opportunity) between which one must choose (in the sense that one cannot do both at the same time, if at all) and can choose. It is that one can be and often is in such a position that, confronted by two or more attractive possibilities (including perhaps the option of ‘doing nothing’), there is nothing either within or outside one’s personal constitution that determines (settles) one’s choice, other than the choosing: Mal. q. 6. This conception of free choice (liberum arbitrium or libera electio) is much stronger than Aristotle’s, on whose conception free choices are free only from external determining factors.”exclusive part of HumanPerson; deliberates, chooses Choice
ChoiceThe practical reason’s free choice of something.
Virtue“To have the virtues is to have a stable and ready willingness to make choices that are morally good because in line with the bonum rationis, the basic good of practical reasonableness. […]
Aquinas firmly holds the Platonic-Aristotelian theses (i) of the connexio virtutum: that to have any of the virtues in its full and proper form one must have all of them, and (ii) of the governing and shaping role of (the good of) practical reasonableness (bonum rationis), that is, of the intellectual and moral virtue of prudentia.”
relates Choice with Good
Prudentia“the master virtue of bringing practical reasonableness into all one’s deliberations, choices, and carrying out of choices – the virtue of prudentia, a virtue both intellectual (of one’s intelligence) and moral (of one’s whole will and character) – is part of the definition, content, and influence of every other moral virtusubkind of Virtue; shared part of ustice, Courage, and Temperance
Justice, Courage, Temperance“Aquinas accepts the Platonic-Aristotelian thesis that there are four virtues which are cardinal, that is on which the moral life and all other virtues hinge or depend: prudentia, justice, courage, and temperantia. Each is a strategic element in one’s integrating of the good of practical reasonableness into one’s deliberations, choices and execution of choices (prudentia), in one’s dealings with others justice), and in integrating and governing one’s desires by genuine reasons (temperantia) and enabling one to face down intimidating obstacles (courage, fortitudo).”subkind of Virtue
Mean“Aquinas accepts Aristotle’s notion that every virtue is a mean between too much and too little, and he constantly stresses that it is reason – with the principles and rules (regulae) it understands – that settles the mean and thus determines what is too much or too little.”characterizes HumanAct
FirstPrinciple“practical reasons (i.e. reasons for action) are propositional: they can be stated as principles and other standards, more or less specific. So principles, ultimately the first principles of practical reason (that is, of natural law), are more fundamental to ethics than virtues are. […]
Ethical standards, for which practical reason’s first principles provide the foundations or sources, concern actions as choosable and self-determining. […]
Practical reason, in Aquinas’ view, has both one absolutely first principle and many truly first principles: ST I-II q. 94 a. 2. […] Aquinas articulates it as ‘Good is to be done and pursued, and bad avoided’ (ibid.).
This has often been truncated to (i) ‘Good is to be done, and evil avoided’ or even, more drastically, (iia) ‘Do good and avoid evil’ or yet more drastically (iib) ‘Avoid evil and seek the good‘”
provides source to PracticalReason; directs to HumanGood
HumanGood“The basic human goods which first practical principles identify and direct us to are identified by Aquinas as (i) life, (ii) “marriage between man and woman and bringing up of children [coniunctio maris et feminae et educatio liberorum]” (not at all reducible to “procreation”), (iii) knowledge, (iv) living in fellowship (societas and amicitia) with others, (v) practical reasonableness (bonum rationis) itself, and (vi) knowing and relating appropriately to the transcendent cause of all being, value, normativity and efficacious action (ST I-II q. 94 aa. 2 & 3). His lists are always explicitly open-ended.”characterizes and directs FirstPrinciple


  • All citations from: Finnis, John, “Aquinas’ Moral, Political, and Legal Philosophy“, The Stanford Encyclopedia of Philosophy (Summer 2020 Edition), Edward N. Zalta (ed.)
  • The Cambridge Companion to Aquinas, CAMBRIDGE UNIVERSITY PRESS, Edited by  Norman Kretzmann and Eleonore Stump, 2010
  • McInerny, Ralph and John O’Callaghan, “Saint Thomas Aquinas”The Stanford Encyclopedia of Philosophy (Summer 2018 Edition), Edward N. Zalta (ed.)

First published: 3/12/2020

[4.9.12] St Thomas Aquinas on Emotions

St Thomas Aquinas (1225 – 1274 AD), in his works Summa Theologiae II-1.22–48 presents a theory of emotions (passiones animae), according to which:

  • Emotions are reactions, changes of the state of the subject initiated by the presence of an object.
  • Aquinas locates emotions in the lower level of the soul, in the sensory appetite (see [4.9.7]).
  • Emotions have a hylomorphic structure (see [1.3.5] and [1.3.7]), where the appetitive reaction is the formal, and the physical reaction is the material element.
  • Aquinas divides emotions into irascible and concuscible sub-kinds and identifies eleven of them.

Aquinas’s model of emotions is represented in the following OntoUML diagram:

Aquinas on emotions
Reaction“In mediæval philosophical jargon, an emotion is a potency whose principle of actualization is external to its subject; in contemporary terms, an emotion is a reaction.” (King)
AppetitiveReaction“In the emotions […] the formal element is an appetitive reaction.” (Aquinas)
“’the lower appetitive power does not naturally tend to anything until after that thing has been presented to it under the aspect of its proper object’ […], since in the case of animals ‘the sensitive appetite is apt to be moved by the estimative power, as when a sheep esteems a wolf as inimical and is then afraid’ The sensitive appetite, as a passive power, is reduced from potency to act when it ‘inherits’ objectual content from the evaluative response-dependent concept (which is the actualization of the estimative power). That is to say, the sheep has an act of the sensitive appetite directed at the wolf, which is presented to the sensitive appetite as a hard-to-avoid imminent evil.” (King)
inseparable part of Emotion; inherits from Reaction
PhysicalReaction“In the emotions […] the […] the material element a physical reaction.” (Aquinas)
Physical reactions can be like: tightness in the chest,
flushing of the face, perspiring etc.
inseparable part of Emotion; inherits from Reaction
EmotionEmotion, according to Aquinas, is an objectual non-volitional affective
psychological state. […] For an emotion is a passio animae, literally something that the soul ‘undergoes’ or ‘experiences’ — a capacity for being in a given psychological state — rather than something the soul ‘does’ (the way it reasons, for instance). In mediæval philosophical jargon, an emotion is a potency whose principle of actualization is external to
its subject; in contemporary terms, an emotion is a reaction.
First, if an emotion is a reaction, it is therefore passive as regards whatever brings it about, that is, whatever prompts the reaction. (King)

“In Aquinas’ theory there is a conception of passion [emotion] which permits him to deal with passions as single events: the hylomorphic approach. At times he deals with it directly: ‘In the emotions […] the formal element is an appetitive reaction and the material element a physical reaction. There is a certain ordered arrangement between the two, in which the physical reaction reproduces (secundum similitudinem) the characteristics of the appetitive reaction’ It would be wrong to concentrate on either side of a passion, to the exclusion of the other. If we try to reduce them to the material side, we will be left with the physiological aspects of emotion, while if we ignore that dimension, passion will have become a quasi intellectual ‘point of view’ which we would take up in a detached style, without any involvement on our part. If we take St. Thomas’ approach and successfully blend the two, then we find that there is a union rather like that between the formal and material side of the subject of the passion, and the various aspects of the emotion will all point, together, at the good of the individual. This union reflects the hylomorphic theory of soul and body; but the passion itself has this structure of matter and form for Aquinas. The material or generic considerations correspond to what is common to all the passions, notably the fact that they involve alteration or exchange of forms and are corporeal; the specific consideration has to do with the identity of each individual passion. This permits Aquinas to say that passions are acts of the sense appetite but also passions of the soul. In St. Thomas’ brief introduction to his treatise on the passions he stresses that he will be studying the ‘passiones animae’, not merely passions of the body. And of course they are passions of the soul, since they belong to the matter soul composite, and so, per accidens, they belong to the soul.” (Gorevan)
has Object; inherits from Reaction
ObjectEmotios have objects, theí are “initialized” by external objects.
“emotion involves a ‘conquest’ of the subject by its object in passion and that this is at home in the appetite, since the appetite acts by being drawn or moved to its object.” (Gorevan)
IrascibleEmotionirascible emotions are directed at objects insofar as they present
something good or evil that might be hard to achieve or to avoid.” (King)
“Aquinas emotion follows perceptual cognition and is definitely evaluative; this is particularly noticeable in the irascible emotions, which are distinguished from one another in terms of intending the object as a good or as an evil.” (Gorevan)
subkind of Emotion
Hope, Despair Hope, Despairsubkind of IrascibleEmotion; are contraries
Courage, FearHope, Despairsubkind of IrascibleEmotion; are contraries
AngerAngersubkind of IrascibleEmotion
ConcuscibleEmotionconcupiscible emotions are directed at objects insofar as they appear to be good or evil” (King)subkind of Emotion
Love, HateLove, Hate
“Cognition is not drawn to things as they are in themselves, but aims rather to generate within us representations of external things. The known, in fact, is drawn to the knower and comes, intentionally, to have the mode of being of the knower. This is why love can achieve greater objectivity, or more exactly, a more complete identity with the being of the object than knowledge can, for it undergoes the influence of things precisely as they are in reality. Love can reach things which cannot (because of the knower’s condition here and now) be known in themselves” (Gorevan)
subkind of ConcuscibleEmotion; are contraries
Desire, AversionDesire, Aversionsubkind of ConcuscibleEmotion; are contraries
Pleasure, PainPleasure, Painsubkind of ConcuscibleEmotion; are contraries


  • Aquinas, Summa Theologiae
  • King, Peter, “Aquinas on the emotions”, in The Oxford Handbook of Aquinas, Oxford: Oxford University Press, 2012
  • Gorevan, Patrick, “Aquinas and Emotional Theory Today: Mind-Body, Cognitivism and Connaturality”, ACTA PHILOSOPHICA, vol. 9 (2000), fasc. 1 – PAGG. 141-151
  • Knuuttila, Simo, “Medieval Theories of the Emotions”The Stanford Encyclopedia of Philosophy (Summer 2018 Edition), Edward N. Zalta (ed.)
  • McInerny, Ralph and John O’Callaghan, “Saint Thomas Aquinas”The Stanford Encyclopedia of Philosophy (Summer 2018 Edition), Edward N. Zalta (ed.)

First published: 26/11/2020