Disillusioned JW:
scholar is correct in saying that 'Porphyry was the first person to introduce the idea that Daniel was not a work of the 6th century but was written much later in the time of the Seleucids in the 2nd century".
Actually, he’s quite incorrect. Porphyry is a known early source for considering interpretations of Daniel by Christians, but not ‘the first person to introduce the idea’. Obviously the original author of the work knew when the work was first written, along with any number of other Jewish sources that may now be lost.
No sources prior to the mid-second century BCE reference Daniel (no, not even Ezekiel, who actually refers to the Ugaritic Danel among two other ancient non-Jews) and it was introduced later than the closure of the ‘Prophets’. Proponents of an earlier writing of Daniel must appeal to magical thinking to ‘explain’ the obvious reference to the Seleucid period.