The Meaning of a Day

I've been thinking a lot recently about the meaning of "a day." With a larger number of my work days starting on one calendar day, when I get in a cab to head out into the night, yet officially beginning in the next calendar day, when I settle into my work station at midnight, I can't say that I'm ever quite sure exactly what day it is. I could say that breakfast, lunch, and dinner still exist, but what, then, do I call the meals between midnight and 8 that help to keep me awake? And is a school pickup at 4pm part of the same day that began at midnight, or is it part of a new day that started after a morning nap? Are days twenty-four hours, or are they simply defined by the hours you are awake within them? And is it possible to live in multiple versions of "a day," being a part of both the hours when others are sleeping and the hours when others are awake?
 
I am sure that at some point, I will begin to know what day it is, and to understand how to manage the days that seem to go on, without much pause, for a week. I am sure that the pieces and parts of sleep will add up to what they need to, at least most of the time, and that perhaps coffee will fill in the blanks. And, in the midst of all of it, I am hopeful that I will remember that a day is not defined just by how many things you do in its hours, but by the difference you have made in some of its minutes.