Paul in one place mentions "the twelve," and he writes of having known Peter and John. Most of the twelve are complete ciphers in both the Pauline and synoptic literature, though some of them are fleshed out in John, which you have already said is unreliable.
Paul mentions the twelve, knew some of them, and is early enough to have known whether or not there actually were twelve. The twelve are attested to in ALL of our traditions. They do not fulfill any particularly christian role, but rather a particularly Jewish role, so there is no reason to suppose them to be a later addition to the tradition. All these facts are difficult to reconcile with the idea that the twelve did not exist. What reason is there to doubt it (and as this is part of your reasoning for doubting the last meal, I would say it is relevant)?
Indeed it does. It's a very appropriate myth, but the question is whether it's historical.
That's exactly the point. It is NOT a very appropriate myth for christianity, only for Judaism. That the "twelve" were retained in christian oral traditions is because they date back to an actual chosen twelve. This twelve fit into the eschatological mission of an apocalyptic jewish prophet, not a christian savior.
Indeed, while there is a tradition of "the twelve" they don't seem to have been at all prominent in the Jesus community, and they are, with few exceptions, nothing but names. Even the names are suspect. The lists are not consistent even among the canonical gospels -- not even among the synoptics. This is an odd state of affairs if they were Jesus' closest followers.
It is an odd state of affairs if the twelve were an invention of the church. They were clearly important in Jesus' mission, important enough to be remembered even when some left the early christian circles. The lists, circulated orally, are remarkably similar, even though many of these names are never mentioned again in stories of the early church.
In other words, you have a tradition in the memory of the early Jesus sect of his twelve chosen followers (which fulfill a Jewish, not Christian agenda), early enough that even someone who knew those that remained attests to it, and yet it is relatively unimportant in later christian tradition. James the brother of the Lord becomes a "pillar" and yet he isn't one of the twelve. Judas is retained in the lists, although he is the betrayer. Everything points to the historicity of the twelve, and it seems that there is no reason to doubt them. The only arguments I have seen (like Crossan's) have more to do with a desire to make Jesus egalitarian (in which case the twelve would not fit). But this is to read into the evidence, not to infer from it.
I believe there are some historical facts in the gospels, but it is absolutely clear that none of them is entirely factual. The difficulty lies in sifting the facts from the whole.
I completely agree. Although I would imagine that I probably am willing to postulate for a greater amount of historical data in the gospels than you are.
Your interpretation requires a great deal of carelessness about the story of Jesus on the part of Paul and his followers
I'm unsure about the followers part (which followers of Paul wrote of this?) but as for carelessness it is simply a mark of orality. A creed such as the one Paul recites is meant to summarize an article of faith in a conveniently memorizable fashion. The importance of Paul's formula is not the context in which it occurs or even the bread or wine itself, but rather how Jesus' words and promises were interpreted by his earliest followers after his death. Whether or not Jesus actually said these words is less defensible than that Paul could have very well known that Jesus' "last supper" was a seder and not used the adjective
azuma in his recitation.
Even if we grant your point, though, it still shows that it if the Last Supper was a seder, that fact was unimportant in the early church.
Not exactly. Many "genres" of oral traditions were transmitted within the early church. Some were transmitted in narrative form, some in parabolic, some in a simple aphorism, some in creeds, etc. I think the Last supper in was transmitted in a narrative form, represented in the gospels, but also as a creed (for different reasons and used differently). As a creed the seder aspect would certainly be unimportant.