Proof.

Let x equal the number of gold
dashes on the highway between me
and your Humboldt dormitory,
between my Complete Works
of Shakespeare and your Periodic Table,
between art and science. Divide
by eighty-seven miles per hour,
the fastest my little black truck can fly
before disintegrating into a shameless mass
of carburetor and fender and slick
upholstery. Add three hours
for the necessary adieu to boyfriend
and roommate, for calling in sick, for washing
the dishes and feeding the cat. Raise that
to the power of your audible tears,
the cracking phone line, my sisterly pain
when you say you have no one
to talk to and then choke on the very truth
of it. The solution, the time until you
can be crying on my shoulder,
the inevitable y, is always less
than the number of minutes before you
no longer need me. Thus, we know that despite
the times you pulled my hair and called
me fat and wished you were an only
child, I love you, quod erat demonstrandum.