Lorenzo Valla, Ars Grammatica 1-12
You see how doctors giving wormwood to children anoint the cup’s rim with Cecropian honey, so that the bitterness covered by sweetness will offend less (for healthy things are often unpleasant to the taste); and you see how song relieves the sailor’s labor as he churns up the blue of the sea with his arms applied to the oars, and the bent ploughman consoles himself by singing. Thus it has pleased me to relate the precepts of Grammar in song, so that soft little ears can be massaged, and so that the heart may drink in the healthy perceptions below the honey; and for that reason I have at the same time added some little bit of resplendence, for there is no poem if the poem be not pleasing.
Aspicis ut medici pueris absinthia dantes
Tingunt cecropio summum cratera liquore
Quominus offendat dulcedine tectus amaror
– nam sunt austero plerunque salubria gustu –
Utque lacertosis pelagi dum cerula verrunt
Remigibus levat ille canor quicunque laborem
Et se solatur cantando incurvus arator,
Sic mihi grammatice placuit precepta referre
Carmine, mollicule demulcerentur ut aures
Pectoraque haurirent sensus sub melle salubres
Nec nihil iccirco simul admiscere nitoris,
Nam nullum fuerit, fuerit nisi carmen amenum.