That itself is a whole another subject in itself, as to whether the "orthodox" Christians who refer to him weren't quoting from recently-made forgeries. Like the Pastoral epistles for example. Do you believe Paul wrote those? Most scholars clearly didn't. Yet we see references to them in Church Father writings. Whether those references themselves are forged is another subject for debate.
I was quoting (being lazy) from an earlier post I made, and that post too was already a copy of something I had written elsewhere to address the argument that Paul never existed. Thus it isn't entirely applicable here. What's important is establishing why we know that 1) Paul did write letters and 2) not all of what we have was written by him (meaning both that their are entire letters which were not authored by Paul, but also that parts of letters he may have or did write are likely not from him).
That's exactly the problem, we these "Methods "nonetheless are still subjective and speculative.
Some, yes. Some, not so much. That is, many analyses used to determine authorship of ancient works, or whether or not one author is responsible for two different works, can be tested. That's how many of them are actually developed: testing writing samples to see if various statistical analyses accurately determine authorship or accurately spot imitation. It's no different in principle, for the most part, than detecting art forgeries or modern imitations. Research in linguistics, psychology, socio-linguistics, textual criticism, communications theory, etc., all show how genre, register, particular media, and individual style (internal lexicon/syntax, literary skill, education, familiarity with the language, etc.) shape any given text. It is often possible to tease out with a high degree of accuracy which of these (or which combination) is responsible for what. Often this makes life more difficult when it comes to ancient authorship, for reasons I already mentioned. Does Plato's lexical usage and idiomatic syntax differ significantly in certain (or all) of his letters because he didn't write them, or because we are comparing them with writings we know are his but which are too different in genre/register to use for comparison? It's hard to tell.
But we don't have that problem with Paul. All we have are letters written to the same type of audience following the same "guidelines" which are "specified" by genre and register. If letters differ significantly, especially in their use of constructions or idiomatic syntax, then we have every reason to suspect different authors. What we find are a number of letters which cohere strongly, and others which don't cohere nearly as strongly either with the "base" or with each other. And we aren't dealing with particularly skillful imitations here either. But that's just language. There are other clues. Do the letters address concerns which are unlikely to have developed during Paul's day, but which we know were an issue for later generations? Are their indications they are written in response to something or with the knowledge of something (e.g., Acts) which Paul could not have known about? And so on.
Statistical and linguistic/stylistic analyses are sound tools for narrowing down the base, and other methods are equally sound when it comes to the probability that a Paul did not write a given component of a letter or write the letter at all. But they only get us so far. Because in some cases there are reasons to doubt, but there are good explanations for these reasons, and thus the issue of authorship in some letters is unresolved, and will remain so.
However, these problems don't exist with Galatians.
However, you say "We have no reason to doubt authorship", and obviously others besides Mcguire (such as those whom he quotes from) have doubted this.
What others? If we're both reading the same paper ("
Did Paul Write Galatians?"), then I'm having trouble finding where others are cited as supporting the author's thesis. First, most of his sources are quite old. Second, the main use of secondary scholarship seems to revolve around whether or not there was a direct literary relationship between Acts and Galatians, but the "one modern scholar" cited who argues that this relationship exist (Enslin, in his 1938 paper) argued that the author of Acts used Galatians (among other letters), not the reverse. The issue is that even granting such a relationship exists, how does one argue directionality (which author used which)?
So if we want to discuss this fully without going too off topic, I think we should make a whole thread devoted to the specifics where we can go over the style, Greek usage, character, manuscript details, etc.
Feel free to start one and link to it here if this post still leaves you with questions or contains much you disagree with/find problematic, and I'd be more than happy to participate. That would (as you say) prevent this thread from straying too far off topic.
Who is and isn't a "Scholar" then?
That of course is subjective. But I think here at the very least we should limit it to those who can actually read ancient Greek and who have read a good deal of modern scholarship on the subject and address it. McGuire begins with what many consider the final nail in an already well-sealed coffin when he discusses the
New Testament Studies article from the 60s which use computer analysis to confirm authorship. But he does not really address those who disagree or their reasons. He moves immediately to a rather radical and definitely dated school of thought beginning with the work of Bauer and continues from this already "out there" approach to something even more radical without ever addressing those who argued against the "Tubingen" school of thought, let alone the reasons for thinking that any direction of literary dependence between Acts and the letters is from the author of Acts' use of the letters, not the reverse.
But they also make contradictions sometimes. See the ending of John, which clashes with the endings of Matthew and Luke.
But that's because John shows no awareness of Matthew or Luke. It's a different tradition. The position you are arguing requires that a later author be aware both of Acts and at least some of the Pauline corpus, and yet deliberately create a disrepency between the two.
We don't have that here because....?
Well if you can think of a good reason that a later christian would go out of her/his way to create this particular disparity, by all means I'd be happy to hear it. But in those texts where we do find disparities which were deliberately created between the written tradition and the text in question, it is quite obvious. For example, in gnostic texts we have Jesus only appearing to die, in direct contradiction to the passion narratives in the gospel. Crossan's theory aside, all of our passion narratives, and certainly most, are dependent at least on Mark or John or both. But the canonical tradition was problematic for later early christian theologies in which Jesus could not have actually died. So texts were written with false authorship claiming something different happened.
It's minor details that we are sometimes able to determine interpolation issues like with Westcott and Horts NWI's from the Alexandrian text.
Minor details are often useful when it comes to whether a particular word or line has been changed. Not in a thesis which posits uses such details to posit that a later author created the work based off of an earlier one, only to disagree with it. So, for example, the fact that Matthew and Luke cohere so well (close to verbatim) with Mark in so many cases makes it quite improbable that there is no literary depedence between the three. The coherence between Matthew and Luke and the Q hypothesis (combined with other arguments) get us directionality (i.e., Mark came first). However, if someone wants to say that, for example, John or Thomas, didn't just use an independent oral tradition, but that the author had some written version of one or more of the synoptics, than the key is to show this through close similarities that can't be exaplained other than by literary dependence. What McGuire does is first argue
for the quite disputed position that the author of Acts knew of the and had read at least some of the Pauline corpus. This is difficult to defend because in order to demonstrate such dependency we would expect more coherence, and where we don't find it, we'd need compelling arguments for why it isn't there (otherwise, there is no argument), yet we don't have that (or at least, few are convinced we do). Even more problematic is to go from taking as demonstrated this dependence and then postulating that it shows the author of Galatians took looks account and changed it. The whole reason for thinking the two are related at all is because of the similarities: one author wasn't just aware of the author, but actually used the other to create his/her work. So if the account is changed, there should be a good reason for the author to have felt that s/he had to 1) use the other text at all, and 2) change it.