All you big fat scholars out there think carpe diem is Latin for "seize the day."
Per diem is just cash and as a tax payer, I don't have a clue what that money is actually for.
This article in The Olympian also reports that the per diem is paid to legislators on "official business", as opposed to, say, a customary bonus for every calendar day during the entire session.
This poetic and metaphysical sphere, somewhere between "memento mori" and "carpe diem", is the space that is at our disposal during our lifetimes, when we are all of us to a greater or lesser extent at the mercy of chance.
The great reason why sinners defer their repentance de die in diem -- from day to day, is because they think God thus defers his judgments, and there is no song wherewith they so effectually sing themselves asleep as that, My Lord delays his coming; and therefore