''Tertium comparationis'' (

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

for "the third artof the comparison") is the quality that two things which are being compared have in common. It is the point of comparison which prompted the author of the comparison in question to liken someone or something to someone or something else in the first place. If a comparison visualizes an action, state, quality, object, or a person by means of a parallel which is drawn to a different entity, the two things which are being compared do not necessarily have to be identical. However, they must possess at least one quality in common. This common quality has traditionally been referred to as ''tertium comparationis''. The most common devices used to achieve this are

metaphor A metaphor is a figure of speech that, for rhetorical effect, directly refers to one thing by mentioning another. It may provide (or obscure) clarity or identify hidden similarities between two different ideas. Metaphors are often compared wit ...

s and

simile A simile () is a figure of speech that directly ''compares'' two things. Similes differ from other metaphors by highlighting the similarities between two things using comparison words such as "like", "as", "so", or "than", while other metaphors cr ...

s, especially, but by no means exclusively, in

poetic language Poetry (derived from the Greek '' poiesis'', "making"), also called verse, is a form of literature that uses aesthetic and often rhythmic qualities of language − such as phonaesthetics, sound symbolism, and metre − to evoke meanings ...

. In many cases one aspect of the comparison is implied rather than made explicit. The New Testament scholar,

Adolf Jülicher Adolf Jülicher (26 January 1857 – 2 August 1938) was a German scholar and biblical exegete. Specifically, he was the Professor of Church History and New Testament Exegesis, at the University of Marburg. He was born in Falkenberg near Berlin ...

, applied the concept of tertium comparationis to the parables of Jesus.

, ''Die Gleichnisreden Jesu'', 2nd ed. (Tübingen: J. C. B. Mohr, 1910) According to Jülicher, a parable or similitude (extended simile or metaphor) has three parts: a picture part (''Bildhälfte''), a reality part (''Sachhälfte''), and the point of comparison (''tertium comparationis'') between the picture part and the reality part. "The kingdom of heaven is like treasure hidden in a field, which someone found and hid; then in his joy he goes and sells all that he has and buys that field" (Matthew 13:44). In this parable, the picture part is the hidden treasure, the reality part is God's kingdom, and the ''tertium comparationis'' is the inestimable value of the kingdom.

Examples

*Necessity is the mother of invention. (English proverb) :Objects of comparison: relationship between mother and child, relationship between necessity and invention :''Tertium comparationis'': source, where something derives from *Woman is the nigger of the world. ( John Lennon) :Objects of comparison: treatment of Black people in US culture, treatment of women in global culture :''Tertium comparationis'': inhumane treatment, subjugation, discrimination *Goodbye, England's rose. ( Elton John on the death of Princess Diana) :Objects of comparison: Diana; roses :''Tertium comparationis'': beauty *If they

ur two souls Ur was an important Sumerian city-state in ancient Mesopotamia, located at the site of modern Tell el-Muqayyar ( ar, تل ٱلْمُقَيَّر) in south Iraq's Dhi Qar Governorate. Although Ur was once a coastal city near the mouth of the ...

be two, they are two so :''As'' stiff twin compasses are two; :Thy soul, the fixed foot, makes no show :To move, but doth, if th'other do. ::( John Donne: "A Valediction: Forbidding Mourning") (Read th
whole poem
) :Objects of comparison: two souls; twin compasses :''Tertium comparationis'': a non-physical link between separate objects that causes action in one to result in action to the other.

References

Rhetoric Semantics {{semantics-stub