Comment by MilStdJunkie

IANAP, but possibly because you're measuring different attributes of the same thing - i.e., mass - but we as a species don't really understand the fundamentals of what mass actually is.

Before ANGRY KEYBOARD SOUNDS commence, I'm not saying we don't know what mass is, I'm saying fundamentals. I.e., why is mass. What causes it to come into being? Bulk entanglement, i.e., a function of probability or "mass as destiny"? Tiny signals? Lots of rubber sheeting? Etc.