Biblical Canon: Open or Closed?

A friend who recently turned Catholic posed this question to me recently. Anyone want to weigh in on it?

Is the canon open, or closed? If open, how then is the Bible the final source for doctrine and practice of the Christian Church? Who knows but what some books may be in the future deleted, and others added in. We cannot have solid dogmatic foundation on such a provisional basis. Karl Barth saw this clearly.

If closed, when was it closed and by whom and by what authority? The position of the writer of the above article is clearly that there was only “provisional” agreement on the canon in the Western Church prior to the Reformation. He points out that Hippo and Carthage were only provisional councils and in this he is most absolutely correct. So then, I assume he means to infer by this that the decisions of those councils do not have universal binding authority. So then, the canon was open to debate even up to the Reformation. I do not deny this either – in a certain sense. But are we in any better of a position today? The question remains: Does or does not the Church catholic (catholic small ‘c’) have an closed canon of scripture? A sola scriptura Protestant, it seems to me, must answer unequivocally “yes”! And we see that most conservative Protestant theologians/pastors/scholars/laymen give this unqualified “yes”. So then, the writer of the above article finds himself in the minority position. If he says that the Protestant canon is correct, true, and closed, then he is leaning on the authority of Protestant concensus. If this authority is not infallible – as Protestants claim it is not – how then is the canon authoritatively closed? You see the dilemma here for advocates of sola scriptura. Leaning on the Bible as anything other than a “provisional authority” is simply unwarranted within the Protestant ecclesial/theological framework. This is the massive cognitive dissonance in Protestantism. In order to lean on the Bible the way that Protestants do, they cannot avoid an appeal to an infallible and unified Church – which is the LAST thing they can, as Protestants, admit. Protestantism is, at it’s heart, self-refuting. Of course, this is the perennial Catholic argument and it has never been more relevant than it is this very day. If the Bible is to be in any way an authoritative message then it is only as authoritative as the messenger. If the Bible is “The Message” of Almighty God and carries with it His total authority, then so must the Messenger who brings it have this same authority.