The commentaries on Dionysius Thrax open, in the Vossiana prolegomena, by asking what a technē is and what use it is to life. The comic Hipparchus is quoted: a technē is the most honourable possession for all men for living. Technē is derived from teuchō; its four kinds are theoretical (astronomy), practical (generalship, aulos, dance), productive (sculpture, cobbling), and mixed (medicine, and grammar with it: it narrates, punctuates, and composes verse). Grammar is useful to orators and philosophers because it dissolves ambiguities by changing times, accents, and breathings — prōtotokos is the child or the mother according to the accent; pais the boy or the earth according to the spelling; a misplaced stop in Iliad 11 makes Nestor or Achilles the old man.
Dionysius is criticised for calling grammar an empeiria (an irrational practice); the defence is that he meant knowledge. Other hosted commentaries in this eul_aid: the Little Commentary, London, Marcian, Vatican scholia, and further text-commentaries.
Hilgard’s Grammatici Graeci is the hosted edition. The slot is that grammatical classroom, not a missing Dionysius.
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