‘Emotion’ is a relatively recent term and there are languages that do not carry an equivalent. Historically, people spoke not of emotions but of passions. The passions encompass, or encompassed, not only the emotions, but also pleasure, pain, and desire.
‘Passion’, like ‘passivity’, derives from the Latin patere, ‘to suffer’. It has often seemed that the passive passions are not within our control, and today the term has come to refer to a powerful or compelling feeling or desire (especially love or lust), while also retaining the more restricted mediaeval meaning of the suffering of Christ on the Cross and the martyrdom of the saints.
The notion of passivity is retained in ‘emotion’, which derives from the Latin emovere, ‘to move out, remove, agitate’. To suffer an emotion is to be acted upon, to be disturbed, and to be afflicted. A long line of thinkers have opposed the ‘animal’ passions to calm and God-like reason, with various authorities from the Stoics to Spinoza going so far as to advocate apatheia, that is, the suppression of feeling, emotion, and concern. Unfortunately, this historical privileging of reason has led not so much to the suppression of feeling as to its near complete disregard. Today, the emotions are so neglected that most people are oblivious to the deep currents that move them, hold them back, and lead them astray.
If I say, “I am grateful”, I could mean one of three things: that I am currently feeling grateful for something, that I am generally grateful for that thing, or that I am a grateful kind of person. Similarly, if I say, “I am proud”, I could mean that I am currently feeling proud about something, that I am generally proud about that thing, or that I am a proud kind of person. Let us call the first instance (currently feeling proud about something) an emotional experience, the second instance (being generally proud about that thing) an emotion or sentiment, and the third instance (being a proud kind of person), a trait.
It is very common to confuse or amalgamate these three instances, especially the first and the second. But whereas an emotional experience is brief and episodic, an emotion—which may or may not result from accreted emotional experiences—can endure for many years, and, in that time, predispose to a variety of emotional experiences, as well as thoughts, beliefs, desires, and actions. For instance, love can give rise not only to amorous feelings, but also to joy, grief, rage, longing, and jealousy, among others.
Similarly, it is very common to confuse emotions and feelings. An emotional experience, by virtue of being a conscious experience, is necessarily a feeling, as are physical sensations such as hunger or pain (although not all conscious experiences are also feelings, not, for example, believing or seeing, presumably because they lack a somatic or bodily dimension). By contrast, an emotion, being in some sense latent, can only ever be felt, sensu stricto, through the emotional experiences that it gives rise to, even though it might also be discovered through its associated thoughts, beliefs, desires, and actions. Despite these conscious and unconscious manifestations, emotions need not themselves be conscious, and some emotions, such as hating one’s mother or being in love with one’s best friend, might only be uncovered, let alone admitted, after several years in psychotherapy.