Legitimate critical scholarship does not assume what we cannot know, and then label it as if it is "the truth! The rules of evidences and proofs in any U.S. Court of Law says, that the claims of a document or contract are to be considered true and binding unless refuted by an adequate presentation of evidences and proofs to the contrary. Also, the plain wording of a text is to be considered as exactly what the author intended to say, and that it is a true witness to the facts, unless absurdity would result, or unless the credibility of the witness has been adequately impeached.
They claim (again a presumption based on the assumption that the supernatural cannot exist...yet they claim to believe in God) prophecy is actually a recording of evidence after a fact to make it appear as if it were supernatural or prescient, but I have shown you one example that cannot be denied already. You see, though most of this school of thought claims to be either Jewish or Christian, they actually do not believe God, and in fact they entirely dismiss the idea of there being anything supernatural. They claim to believe in God, but simultaneously claim that they do not believe that if there is a god, or that he/she/it would ever bother with becoming personally involved with the History of this world, let alone us flyspeck individual humans. Thus, any kind of, what they would define as, supernatural intervention in human history, is a closed book to their closed minds. It appears they are not genuine believers but rather make-believers!
An additional way that the Book of Daniel is a witness of the book of Isaiah being one scroll, is the dual inferences to comments in Isaiah from later and earlier passages. In Chapter 9, Daniel refers to the time of the restraining of Israels apostasy and rebellion (Isaiah 59:20/Tritto), the rebuilding of the City of Jerusalem (Isaiah 44:28/Deutero), and culmination after 70 weeks of years and the birth of Messiah and the ceasing of sacrifice for sin after He is cut off (Isaiah 53:8/Tritto). Eventually sinning would cease in Jerusalem (Isaiah 27:9/Uno), and there would be a subsequent, eventual coming age of Gods righteousness (Isaiah 1/again Uno). All this testifies to sections 1, 2, and 3, as all being one Scroll before the time of the end of the Medo-Persian empire, before the time of Cyrus, and is an amazing, serious, piece of evidence as to the actual outside of the natural order prescient nature of the text of Isaiah!
in John 12, we have a quote from the latter part of the Book of Isaiah followed by the connective phrase, and that Isaiah also said, and then finishes with a quote from the early section of the Prophets book. The word also clearly identifies the opinion of John the Apostle, and thus that of Yshua (Jesus the Christ), that both sections are from the same author and the same book.
Again in Pauls letter to the Romans, from chapter 9 through 11, the shrewd Lawyer Rabbi Shaul (Saint Paul) does the exact same thing more than once, and even Yshua Himself, whom they call the Lord, quoting extensively from Isaiah, draws no lines of distinction between authors or sections.
Finally, in this regard we see the same pattern of confirmation present in the writings of the early Church fathers. In Justin Martyrs, First Apologia, Chapter 35, Justin tells us, There are the following predictions: Unto us a child is born, a Son is given... citing Isaiah 9:6, and then turns around and says, and again the same Prophet Isaiah being inspired by the prophetic Spirit said, I have spread out my hands to... quoting from Isaiah 65:2! Note carefully the connective phraseology ...and again the same Prophet Isaiah, being inspired by the..., connecting the first part of the book of Isaiah to the last part, under one author.
So if Isaiah was a lie or a contrived hoax, then this means Jesus was deceived by it as well and could not possibly be the Messiah. John was so fooled as was Paul and Justin was in fact taught the deception. Do you really buy these possibilities? And why isn't Sayre weighing in?
Think on these things...
In His love
Paul