In the title "Ars Goetia," is "Goetia" an appositive noun?

Question

Ars Goetia is a well-known book about demonology written in Mediaeval Latin. I'm having trouble analyzing the grammatical structure of the title. Ars is a feminine noun in the singular nominative form. Goetia looks like it is feminine and in the singular nominative form. However, I'm not sure how it relates grammatically to Ars.

I looked up the entry for ars in Lewis and Short, and it seems to say that it is generally modified by an adjective (e.g. ars gymnastica) or a noun in the genitive case (e.g. ars disserendi). Goetia is obviously not a genitive form, but I also wouldn't think it would be used as an adjective: it's a loanword from the Greek noun γοητεια (I would expect the corresponding adjective to be something like Goeticus/-um/-a).

To me, it seems like it is an appositive noun. Am I right? If so, are there examples of this construction being used with ars in Classical Latin? And are there any differences in meaning, or other reasons to use the title Ars Goetia instead of Ars Goetiae or Ars Goetica?

One reason I suspect the author intentionally used an appositive noun after ars here is because a few of the other books in the Lesser Key of Solomon also seem to be titled this way, such as "Ars Theurgia-Goetia" and "Ars Almadel." But there is also a book that seems to have the structure with an adjective, the "Ars Paulina."

Answer 1

I'd say goetia is clearly a noun, as you say. Some points to consider:

1. Nouns are sometimes used as adjectives: victor exercitus -- the victorious army (A&G, § 321 c);

2. There was some confusion as to what this word actually referred to.

   See, e.g., Du Cange's entry:

   Getia, Maleficiorum doctrina. Glossae antiq. Forte pro γοητεία, [vel forte a Geta mago celeberrimo, quem diu in AEgypto commoratum fuisse narrat Strabo lib. 7. Papias editus et MS. habet: Gethia, maleficiorum doctrina, Gheticus, Thracus. Vide Gitta.] {The entry on gitta refers to praestigiae per manuum invocationem, maleficia.}

   And then there's Augustine, who contrasts it with theurgy (both under 'magic') in Civ. 10.9 (or, as in Jensen's 1475 edition):

   Fiebant autem simplici fide atque fiducia pietatis, non incantationibus et carminibus nefariae curiositatis arte compositis, quam uel magian uel detestabiliore nomine goetian uel honorabiliore theurgian uocant, qui quasi conantur ista discernere et inlicitis artibus deditos alios damnabiles, quos et maleficos uulgus appellat (hos enim ad goetian pertinere dicunt), alios autem laudabiles uideri uolunt, quibus theurgian deputant; cum sint utrique ritibus fallacibus daemonum obstricti sub nominibus angelorum.

3. Medieval authors sometimes like to give a 'Greek' flavour to their titles, especially when they are writing something esoteric. But even 'conventional' authors sometimes couldn't resist Anselm's Monologion and Prosologion come to mind, for example.

Answer 2

As you say, γοητεία “sorcery, witchcraft” is a noun. Apparently some mediaeval Latinist mistook it for the feminine singular nominative of an adjective. Classical Latin does have words like “musica” as a synonym for “ars musica”, so it could be that someone thought you could equate “goetia” with “ars goetia”, but this could only work if goetia were an adjective. Which it is not.