Seneca the Elder, Suasoriae 2.13, 540 M
“The grammarian Procellus used to claim that [Severus’] line was a solecism because, although he indicated many were speaking, he used to say “this is my day” instead of “this is our day”. And in this he was carping at the best part of a great poem. For, it is feeble if you make it “our” instead of my—all of the verse’s elegance will disappear.
For its greatest decorum is in this line and it comes from the vernacular (for, “this is my day” is something like a proverb). If, in addition, you reconsider the sense, then the grammarian’s pedantry—which should be kept away from all of the better minds—has no place at all. For, they did not all speak together as a chorus might with a leader guiding them, but each one spoke individually, “this is my day.”
Illud Porcellus grammaticus arguebat in hoc versu quasi soloecismum quod, cum plures induxisset, diceret: “hic meus est dies,” non: “hic noster est,” et in sententia optima id accusabat quod erat optimum. Muta enim ut “noster” sit: peribit omnis versus elegantia, in quo hoc est decentissimum, quod ex communi sermone trahitur; nam quasi proverbii loco est: “hic dies meus est”; et, cum ad sensum rettuleris, ne grammaticorum quidem calumnia ab omnibus magnis ingeniis summovenda habebit locum; dixerunt enim non omnes simul tamquam in choro manum ducente grammatico, sed singuli ex iis: “hic meus est dies.”