The definition of "empty calories"

Well, if we want to get philosophical, you are right. However there is a big difference between a calorie that contains essential nutrients and a calorie that has nothing but simple sugars in it. So it's a matter of semantics. I don't consider the calories from a Coca-Cola beneficial for me, so to me they are empty. Your mileage may vary.

Its not philosophy or semantics to be precise about meaning.  Words have specific meanings.  In terms of providing energy that your body can convert to power to do work, calories are equivalent, be they from Coke or a plate of macaroni and cheese.  Your muscles cannot tell the difference.

In order to have a broader discussion about the nutritive value of foods, it is necessary to recognize what calories measure and what they do not.  In fact, there are lots of things in food that are important that do not appear on the standard government-mandated "nutrition" labels.

Ok.