> At least, though, the calendar is not simply being arbitrary and imposing artificial parameters to the world around us. Minutes, hours, and weeks may be manmade, but days, years, and seasons are not.

Why do you say weeks are manmade, I wonder? Presumably our week is patterned after the first week of creation laid out in Genesis 1:1 - 2:3.

Even the term "hour" is used in the Bible, although I don't know that it refers to the literal 60-minute period of time we think of as an hour. Then again, maybe it does, since in some cases it seems to be referring to the position of the sun in the sky. That doesn't necessarily mean it isn't manmade, though.

I would definitely argue that the seven-day week was instituted by Someone other than man, however. :)