3. The perplexity thus set up is greatly deepened when we remember that the period assigned to the earlier prophets is near the beginning of the known age of alphabetic writing, [363] and before the known age of writing on scrolls. A herdsman of Judea, with a classic and flowing style, is held to have written out his hortatory addresses at a time when such writing is not certainly known to have been practised anywhere else; [364] and the pre-eminent style of Isaiah is held to belong to the same period. "His [Amos's] language, with three or four insignificant exceptions, is pure, his style classical and refined. His literary power is shown in the regularity of structure which often characterizes his periods ... as well as in the ease with which he evidently writes.... Anything of the nature of roughness or rusticity is wholly absent from his writings" (Driver, Introd. to Lit. of Old Test. ch. vi, § 3, p. 297, ed. 1891). Isaiah, again, is in his own narrow field one of the most gifted and skilful writers of all antiquity. The difficulty is thus nearly as great as that of the proposition that the Hebrew of the Pentateuch is a thousand years older than that of the latest prophetical books, whose language is substantially the same. (Cp. Andrews Norton, The Pentateuch, ed. 1863, pp. 47-48; Renan, Hist. des langues sémit. 2e édit. p. 118.) 4. The specialist critics, all trained as clergymen, and mostly loth to yield more than is absolutely necessary to skepticism, have surrendered the antiquity claimed for Joel, recognizing that the arguments for that are "equally consistent with a date after the Captivity." [365] One of the conclusions here involved is that "Egypt is probably mentioned only as the typical instance of a Power hostile to Judah." Thus, when we remember the later Jewish practice of speaking of Rome as "Babylon," or "Edom," allusions by Amos and Hosea to "Assyria" have no evidential force. The same reasoning applies to the supposed ancient portions of Isaiah. 5. Even on the clerical side, among the less conservative critics, it is already conceded that there are late "insertions" in Amos. Some of these insertions are among, or analogous to, the very passages relied on by Kuenen to prove the lofty monotheism of Amos. If these passages, however, suggest a late date, no less do the others disparaging sacrifices. The same critics find interpolations and additions in Hosea. But they offer no proof of the antiquity of what they retain.