In his unpublished notes on ‘little epic’ from the middle or late 1950s, McLuhan makes these interesting points regarding Plato:

• “There is nothing that was later known as idyll and epyllion in Alexandria that was not familiar to Plato and Aristotle.”
• “There was nothing new about little epic to Plato and Aristotle — the Platonic dialogues can be read as epiphanies of truth obtained in the ritual tracing of the labyrinths of dialectic.”

A decade or so later, in ‘Toward an Inclusive Consciousness’, 1967:

Plato and Aristotle, the representatives of the new literate culture of Greece in philosophy, had this same doubleness. They straddled the written and oral traditions. They translated the tribal encyclopedia of the preceding culture into the written, classified form.¹ 

The same point is made regarding Aristotle in Laws of Media:

Aristotle and others were working with one foot in each world, as it were, using the new forms of [literate] awareness but trying to retain or update the ideas of the old oral culture. (33)

‘Doubleness’ was the central characteristic of the little epic (epyllion) for McLuhan. In his view its labyrinthine character amounted to a resonance between distinct plots, styles and lessons. ‘Dialectic’ in Plato could be seen as the attempt to instill acquaintance with this resonance — via this resonance.