Altare, from altos, high; some ancient etymological guesses are recorded by St Isidore of Seville in Etymologiae xv.
Varro's etymologies could be only a priori guesses, but he was well aware of their character, and very clearly states at the outset of the fifth book the hindrances that barred the way to sound knowledge.
He was the first to lay down and apply sound rules of criticism and emendation, and to change textual criticism from a series of haphazard guesses into a "rational procedure subject to fixed laws" (Pattison).
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