Since the time of Wolf there has been one point in the ‘higher criticism’ of the Homeric poems on which all scholars have been agreed: it is that in the ninth century B.C. there was no reading public in Greece. Further, since the time of Wolf, the majority of critics have assumed, without attempting to prove, that a poem can be delivered orally only if it is short enough to be delivered at a single sitting; and that a longer poem is by its very length shown to have been designed for a reading public and not for oral delivery. No one maintains that the Iliad, as we have it, could be recited at a single sitting (except Buchholz, Vindiciae Carm. Hom. I. 8). It follows therefore that the present shape of the Iliad is due to the demands of a reading public; and that if there was an Iliad at all in the ninth century, its length must have been such as was compatible with the conditions of an oral delivery. To account for the evolution of the Iliad as we have it, from a poem or poems short enough to be recited at a single sitting, various theories have been proposed. They may be distributed into two classes: theories of aggregation, and theories of expansion. According to the former class, the Iliad is an aggregation of lays or ballads, composed independently of each other by different poets, but related to the same subject, and exercising a natural attraction on each other. The theory of aggregation is based on the analogy of what was supposed, but is now denied, to have occurred in the history of other literatures; it is not based on a study of the conditions under which literature developed in the earliest Greek times.