St Thomas Aquinas ( “Doctor Angelicus”, 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:

Class | Description | Relations |
---|---|---|
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 |
Emotion | “Emotion, 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 |
Object | Emotios 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) | |
IrascibleEmotion | “irascible 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, Despair | subkind of IrascibleEmotion; are contraries |
Courage, Fear | Hope, Despair | subkind of IrascibleEmotion; are contraries |
Anger | Anger | subkind of IrascibleEmotion |
ConcuscibleEmotion | “concupiscible emotions are directed at objects insofar as they appear to be good or evil” (King) | subkind of Emotion |
Love, Hate | Love, 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, Aversion | Desire, Aversion | subkind of ConcuscibleEmotion; are contraries |
Pleasure, Pain | Pleasure, Pain | subkind of ConcuscibleEmotion; are contraries |
Sources
- 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