1. Itinerant professional teachers lecturing on a variety of subjects, but generally offering advice on how to succeed in public life: see p. 215.

2. ‘Guinea-pig’: the Greek has ‘put a Carian at risk’. Caria, in south-west Turkey, was a traditional source of slaves and mercenary soldiers, both of which classes were regarded as expendable relative to citizens; cf. Euthydemus 285c. ‘Run before you can walk’: the Greek has ‘begin pottery by making a wine jar’, too large a piece for a novice.