Gellius, Attic Nights 13.31
“The words of the passage, in which we find the proverb caninum prandium (a dog’s dinner) are these: ‘Do you not see that Menestheus lists three types of wine, including the black, white, medium (which they call kirron) as well as new, old, and medium? And further, that the dark one produces virility, the white one is a diuretic, and the medium is a digestive aid? Still more, that the new one cools you down, the old one heats you up, and the middle is a dinner for a dog (caninum prandium)?’
We investigated for a long time just what was meant by ‘dinner for a dog.’ An abstemious dinner – that is, one without wine – is called a ‘dinner for a dog’ because dogs do not drink wine. Therefore Menestheus named it ‘medium wine,’ because it is neither new nor old – and many men speak thus, as though every wine were either new or old – and he indicated that the medium wine had none of the power either of the old or the new wine, and was on that account not to be considered wine at all, because it could neither cool one down nor heat one up.”
Eius autem loci, in quo id proverbium est, verba haec sunt: “Non vides apud Mnesitheum scribi tria genera esse vini, nigrum, album, medium, quod vocant kirron, et novum, vetus, medium? et efficere nigrum viris, album urinam, medium pepsin? novum refrigerare, vetus calefacere, medium esse prandium caninum?” XV. Quid significet “prandium caninum”, rem leviculam diu et anxie quaesivimus. XVI. Prandium autem abstemium, in quo nihil vini potatur, caninum dicitur, quoniam canis vino caret. XVII. Cum igitur “medium vinum” appellasset, quod neque novum esset neque vetus, et plerumque homines ita loquantur, ut omne vinum aut novum esse dicant aut vetus, nullam vim habere significavit neque novi neque veteris, quod medium esset, et idcirco pro vino non habendum, quia neque refrigeraret neque calefaceret.
For any readers engaging (engorging) in non-canine dinners tomorrow, I hope that you avoid the fate of the earliest wine drinkers (depicted in this 3rd century mosaic from Cyprus), particularly the guy in the bottom right!