But what does this have to do with sola scriptura? The idea is this. Summarizing an early Jesuit critique of the Protestant doctrine, Feyerabend notes that (a) scripture alone can never tell you what counts as scripture, (b) scripture alone cannot tell you how to interpret scripture, and (c) scripture alone cannot give us a procedure for deriving consequences from scripture, applying it to new circumstances, and the like. Let’s elaborate on each and note the parallels with modern empiricism.
First, there is no passage in any book regarded as scriptural that tells you: “Here is a list of the books which constitute scripture.” And even if there were, how would we know that that passage is really part of scripture? For the Catholic, the problem doesn’t arise, because scripture is not the only authoritative source of revealed theological knowledge in the first place. It is rather part of a larger body of authoritative doctrine, which includes tradition and, ultimately, the decrees of an institutional, magisterial Church.I agree the idea that you simply look something up in the Bible to find answers doesn't work. Protestants I've heard say "Bible interprets Bible." Well Bible interprets Bible to produce all sorts of contradictory understandings.
I sometimes have a hard time distinguishing between Sola Scriptura and fideism. I'm something of an expert on the political theology of the American Founding. While there were orthodox Trinitarians, deists, unitarians and folks all over the spectrum among them, the prevailing political theology rejected fideism and incorporated "essences" in nature as a necessary component for proper theological understanding (and it tended to be in nature, not in special revelation where they parked the public issues).
So here is James Wilson on how the Bible though it contains truth is an incomplete book:
But whoever expects to find, in [Scripture], particular directions for every moral doubt which arises, expects more than he will find. They generally presuppose a knowledge of the principles of morality; and are employed not so much in teaching new rules on this subject, as in enforcing the practice of those already known, by a greater certainty, and by new sanctions. They present the warmest recommendations and the strongest inducements in favour of virtue: they exhibit the most powerful dissuasives from vice. But the origin, the nature, and the extent of the several rights and duties they do not explain; nor do they specify in what instances one right or duty is entitled to preference over another. They are addressed to rational and moral agents, capable of previously knowing the rights of men, and the tendencies of actions; of approving what is good, and of disapproving what is evil.Wilson ends the discussion by asserting "that the scriptures support, confirm, and corroborate, but do not supercede the operations of reason and the moral sense."
The "operations of reason and the moral sense" were to Wilson among other things the teachings of the Scottish Common Sense Enlightenment in which he was imbibed. He could incorporate those truths into his theology just as Aquinas incorporated Aristotle.
This is a rejection of fideism. Is it a rejection of Sola Scriptura? Perhaps. Though I have learned that there is a much neglected tradition of the natural law in orthodox Protestantism (it goes without saying that such tradition exists in unorthodox, freethinking Protestantism too).
So if "the Bible alone" is insufficient, there is always the natural law as an added component to achieve a holistic understanding.
But this still does not solve the dilemma posed by Feser. On a personal note -- the approach that I am sympathetic to -- is the most radical Protestant one: The Quakerish approach. And that is to concede everything Feser and critics of Sola Scriptura note and conclude there is no problem. That's because it's up to the individual -- radical priest that she is -- to determine for herself how to understand, including which books are inspired, what they mean, and whether there are errors in them.
Now, it should be done "in good faith" according to the dictates of conscience. And truth is what it is. You don't just get to make stuff up. There are a lot of learned folks out there who will call you out if you do.
But this is how William Livingston, a Quakerish American Founding Father put it in the context of explaining to a then prominent member of the religious right why the Bible/Christian religion would not be part of the organic "higher law" of the Articles of Confederation/the United States:
[A]nd to have made the 'law of the eternal God, as contained in the sacred Scriptures, of the Old and New Testament, the supreme law of the United States,' would, I conceive, have laid the foundation of endless altercation and dispute, as the very first question that would have arisen upon that article would be, whether we were bound by the ceremonial as well as the moral law, delivered by Moses to the people of Israel. Should we confine ourselves to the law of God, as contained in the Scriptures of the New Testament (which is undoubtedly obligatory upon all Christians), there would still have been endless disputes about the construction of the of these laws. Shall the meaning be ascertained by every individual for himself, or by public authority? If the first, all human laws respecting the subject are merely nugatory; if the latter, government must assume the detestable power of Henry the Eighth, and enforce their own interpretations with pains and penalties.The bold face is mine.
For your second article, I think there could be no occasion in the confederacy, provision having been made to prevent all such claim by the particular constitution of each State, and the Congress, as such, having no right to interfere with the internal police of any branch of the league, farther than is stipulated by the confederation.
To the effect of part of your third article, that of promoting purity of manners, all legislators and magistrates are bound by a superior obligation to that of any vote or compact of their own; and the inseparable connexion between the morals of the people and the good of society will compel them to pay due attention to external regularity and decorum; but true piety again has never been agreed upon by mankind, and I should not be willing that any human tribunal should settle its definition for me.
Livingston is sympathetic to the notion that each individual decides for himself how to understand the Christian religion. Therefore any and all human laws that try to properly understand, define or Livingston's actual word "respect" Christianity are nugatory.
It's a good argument as to why America was not founded to be a "Christian nation."