There is a good chance that at some point today you will hear the phrase, "beware the Ides of March." Heck, you might even say it yourself. But why do we say it?

In spite of the plural form, in this sense it is usually used with a singular verb in English. The word is from Latin idus, and probably of Etruscan origin. It's interesting to note that the Romans never would have said the "15th of March." Months had three "nodal points": Kalends (the first day), Nones (the ninth day), and Ides. To refer to any day in the month other than these, a Roman would count backwards from the nearest nodal day our  March 13th, for example, would be "three days before the Ides of March" (they included the nodal day in their backward count), and our March 16th was "17 days before the Calends of April" ("ante calendus Apriles"). Not until the Emperor Constantine issued an edict in 315 (was the system abolished in favor of using weeks with unnamed, though numbered, days.

The crowd arrives, and scattered here and there over the green grass they drink, every lad reclining beside his lass…But they grow warm with sun and wine, and they pray for as many years as they take cups, and they count the cups they drink…There they also sing all the songs they learned in the theater, beating time to the words with their hands…they stagger home, a public spectacle: 'How happy you are!' cries the crowd as they meet them."

Sounds like a pretty good time. And so — in the original, festive spirit of the Ides of March — we finally come to the real reason why the Curiosity Desk decided to write about this today. It gave us an excuse to feature this: