"We all agree that there are the differences, but these do not necessarily demand another authorship. Isaiah is versatile, and doubtless had several styles. His long experience would give him fluency of expression, and these later prophecies belong to his quiet years of retirement, at the close of his political career. Now if Isaiah, after writing his account of Sennacherib's invasion, had retired from active life, and spent about twenty years in restful meditation, and then reappeared in literary life with his mind filled with Messianic prophecy, and a deeper spirituality, is it not highly probable that this later thought would be presented in different style and language? Compare the busy sermons of a busy preacher, in a populous working-class district, with those preached in life's later retirement of quiet thought, balanced conclusions and deeper spirituality."
"Consider again the different style of authors. Would anyone have thought that The Pickwick Papers and The Tale of Two Cities were both from the pen of Charles Dickens; or The Lord of the Isles and Kenilworth by Sir Walter Scott? But all the differences in the Book of Isaiah are consistent with his authorship."

(p. 223) "But are these critics, by their rules, able to detect the different authors? We cannot do it today. Tate and Brady together wrote the hymn, 'As pants the hart for cooling streams,' who is going to tell us how much is by Tate, and how much by Brady? Sir W. Robertson Nicoll tells of Robert Louis Stevenson collaborating with Lloyd Osborne in a certain novel. Professor Neil, of Cambridge, was confident that he could detect the parts which each had written. When his decisions were taken to the one who had arranged the novel, Neil was wrong in nearly every decision. But if the critics fail in modern literature, what of 2,650 years ago? We shall have need of better proof before we swear allegiance to Isaiah II."