This interdiction, overly dogmatic and itself perhaps misplaced, sprang from an irritation with the excesses and lack of rigour of much current source-hunting. Leonard Digges' assertion ‘look thorough / This whole book, thou shalt find he doth not borrow / One phrase from Greeks, nor Latins imitate’, even if we regard it as false or misleading, must at least have seemed plausible to many of Shakespeare's early readers (Dr Johnson later made a not dissimilar claim). Still, there can be no reasonable doubt that Shakespeare read some Virgil in Latin at school, and that allusions and references to Virgil are found throughout his work. No one has undermined the demonstration by Root, made more than a century ago, that Shakespeare's classical mythology derives primarily from Ovid and Virgil, Ovid's influence being four times greater than Virgil's. The main focus of Shakespeare's interest in Virgil was in three episodes from the Aeneid, the tragedy of Dido, the sack of Troy, and Aeneas' visit to the Underworld (episodes that have been favourites throughout history, from St Augustine in his Confessions onwards). Whether Shakespeare read the second half of the poem, either in Latin or in the translation of Phaer and Twyne (1584), cannot be proved, though it is likely enough.