She knows you already because of two things.

Joost Burgi, late in the 16th century, was the first one who discovered logarithms. Sadly, some cat named John Napier published first and got all the accolades. Fortunately for Joost, he had some other tricks up his sleeve: like inventing the minutes hand on the clock in his studio during spare time...Think of days before this clockmaker. One hand spinning around per hour. No frame of reference for the subtleties or the nuances in a classroom with friends or a workplace with fellow bees or a bedroom laying naked with your lover. Like taking away the sound of immediacy. How do you feel about that? You'd have to trust the urgency in your body to push, pull or linger. A young boy before Joost sitting with a girl wanting to tell her what he's been feeling and having to trust his body time for measure...Read a book this afternoon called "Identical Strangers" written by a freelance writer and filmmaker. Lovely and sweeping but a shame we need books to reassure us what we already know. There are already people who know you. You've always been connected to them...*optimism* Tomorrow I'll be sitting in the DMV. Will forget the minute hand as to save myself the tension from the details within the minutes...If I could cut out the second hand on my wall clock and html a code to block the minutes on my blackberry, I would. I'm well aware everything important is made alone (or with your most beloved) in a dusty, unkempt studio, real or imagined.

"Imagine a slightly different version of you walks across the room, looks you in the eye and says “hello” in your voice. You discover that she has the same birthday, the same allergies, the same tics, and the same way of laughing. Looking at this person, you are able to gaze into your own eyes and see yourself from the outside. This identical individual has the exact same DNA as you and is essentially your clone.
We don’t have to imagine."
–From "Identical Strangers"