Thomas Aquinas's account of analogy (ST 1.13.10)
Univocal terms mean absolutely the same thing, but equivocal terms absolutely different; whereas in analogical terms a word taken in one signification must be placed in the definition of the same word taken in other senses; as, for instance, "being" which is applied to "substance" is placed in the definition of being as applied to "accident"; and "healthy" applied to animal is placed in the definition of healthy as applied to urine and medicine. For urine is the sign of health in the animal, and medicine is the cause of health.
This translation is a little misleading, in that the way it translates Aquinas's claims makes it sound more static than it is -- Aquinas's account of analogy does not apply to terms as such, and in the Latin he does not talk about 'univocal terms', for instance, but about 'univocals'. Aquinas's univocal, equivocal, or analogical is applied to predication, or things like imposition of names, which can be thought of along the lines of predication. In other words, it is about what we would call use of terms, application of them to something. Nor is it a single application; Aquinas's account is about comparison of one use with another. Nothing is univocal on its own, but only in comparison with something else.
To apply a term univocally means that it is in all the uses being considered omnino eadem ratio, wholly the same notion; to use a term equivocally means that it is in the uses considered omnino ratio diversa, a wholly different notion; and to use a term analogically (i.e., by a kind of proportion) is in between the two. One of the examples Aquinas gives of analogical use is that of 'animal' applied to an animal and a painted animal. If I have a cow and I paint the cow, I can point to the cow and say that it is a 'cow'; I can also point to the painting and say that it is a 'cow'. This use is not univocal; a cow is not a painted cow. Nor is it equivocal; there is something shared by meanings of the word as I am using it. As Aquinas puts it, real cow is in the definition of painted cow; that is, a painted cow is a cow in the sense that it is an image of a real cow. This is, of course, not a bare claim about words; it is a claim about how things are understood.
Aquinas gives other examples of analogical use, but there's a reason to focus a moment on the painted animal example, because it connects to a theological topic that is not often considered in conjunction with analogical use of names: veneration of icons. That the two relate can be seen by considering the works of St. Theodore the Studite on the subject.
Theodore (759-826) was a monk in the Stoudios Monastery, one of the great monasteries of Constantinople. He was the most important figure on the orthodox side in the dispute that arose during the Second Iconoclasm. Veneration of icons had been approved by the Second Council of Nicaea in 787, but Emperor Leo V saw himself as reliving the greatness of the Isaurian Dynasty (the sources of the First Iconoclasm) and tried to revive their iconoclastic policies. The orthodox Patriarch Nicephorus was exiled; a new Patriarch sympathetic to the Imperial policy was put into place, and St. Theodore became the major opponent of the iconoclastic movement. He was exiled, but conducted a massive correspondence campaign that had considerable influence. When the iconoclastic policy ended after his death in 843 (which is celebrated by the East under the name 'Triumph of Orthodoxy'), it was Theodore above all who was remembered.
The issues intersect when we consider veneration of icons. In effect, if we have an icon of Christ, and I address it in prayer by saying, "O Christ", then if the use of the term 'Christ' is equivocal (compared to the use of 'Christ' to mean Christ Himself), I am not praying to Christ, but if the use of the term is univocal, I am praying to a painting as Christ. Both of these are idolatrous. Theodore has the means to address this in his First Refutation of the Iconoclasts:
...the copy is not separated from the glory of the prototype, in the same way as shadow is not separated from light. And indeed, whatever is said about the cause, the same things can be said without exception of whatever is caused. In the former case, this will be said in the proper manner (kyrios), because it is so by nature (physei); in the latter case, it will not be said in the proper manner (kyrios), but rather by homonymy (homonymos)....And we call the image of Christ "Christ," because it is also Christ, and not two Christs--since it is impossible to distinguish one from the other in virtue of the name (homonymia), but only in virtue of the nature (physei); so the blessed Basil says that the image of the king is also called king, and there are not two kings; neither is power divided, nor is the glory apportioned; and the honor of the represented images goes over (diabainei) to the prototype. [Theodore the Studies, Writings on Iconoclasm, Cattoi, tr. Newman Press (New York: 2015), pp. 51-52.]
...when you consider the likeness to the original by means of a representation (di'ektypomatos), you will see both Christ and the image of Christ. However, it will be Christ by virtue of homonymy (kata to homonymon); it will be the image of Christ because of the relation (kata to pros it). For the copy is a copy of the original, and so the name is the one name of the one who is named. [p. 54]
'Christ' used of Christ and the icon of Christ cannot be univocal: they differ by nature. But it cannot be simply equivocal, either, because the term is used of one because of its relation to the other as an image, just as the image of the emperor is also called the emperor. It is precisely that makes it possible for the honor of the one to pass over to the other, and also why this does not mean that anyone is honored other than Christ, just as the image of the emperor and the emperor are not two emperors. The icon is not venerated as different from Christ; and it is not venerated as Christ in its own nature; but it is venerated as Christ insofar as it is understood that it is of Christ. Veneration of icons depends on the analogical use of terms.
Various Links of Note
* "Reading Acts" has a series on IV Maccabees: What is Fourth Maccabees?, Fourth Maccabees and the Fourth Philosophy, Fourth Maccabees and a Rational Faith. With regard to the last, I think we need a broader view, since it is not just temperance but all of the four cardinal virtues; I've touched on this, but only touched on it, in my post on The Philosophical Vindication of Judaism in IV Maccabees.
* Natalie Wolchover, A Long Sought Proof, Found and Almost Lost
* Phoebe Maltz Bovy, The Perils of 'Privilege'
* An interesting phenomenon is what is often known as the Mandela Effect: it occurs when, independently, a significant number of people misremember the same thing in the same way, and do so very vividly. It gets its name from the claim that lots of people remember Nelson Mandela dying in the 80s instead of in 2013, but a more plausible example of it is that people will swear up and down that the name of the Berenstain Bears is the Berenstein Bears, to the extent that, if shown the actual name, they will often think it was changed at some point. Another common example is that a great many people remember the comedian Sinbad having made a genie movie named Shazaam, despite the fact that he never did so. (There was a movie named Kazaam with Shaquille O'Neal, but there are apparently people who remember that and also remember a Sinbad movie named Shazaam.) Sinbad apparently gets asked about it constantly, so for April Fool's this year, he worked with College Humor to make 'proof' of the nonexistent movie.
* A good YouTube analysis of how Who Framed Roger Rabbit? achieved its unusually good meshing of live action and animation.
Christ Our Pascha: Catechism of the Ukrainian Catholic Church
Donald Ainslie, Hume's True Scepticism
George Santayana, Three Philosophical Poets
Michael Flynn, Eifelheim