I think that in the interest of NPOV we should change all references to days of the week to First Day, Second Day, Third Day, Fourth Day, Fifth Day, Sixth Day, and Seventh Day.
Oh, wait... that would be imposing a Quaker POV. Never mind.
Not to mention the anti-programmer bias! Without a Zeroth Day we'd be forever hitting fence post errors and the stack-heap collisions on Seventh Day would not be worth thinking about.