Living by the Numbers
Credit: Illustration by Eddie Guy
Do I want to live my life strapped into a heart monitor, or logging the calories in every square of dark chocolate I eat? No. I like to think of myself as more than the sum total of the bodily functions that I can quantify. But I sure do like the results of the quantification.

Scientists talk about the observer effect, that the very act of observation changes what's being observed. There's something obvious and ancient about this – it's why God is pictured up in heaven, watching over us. Just the idea of someone watching does the trick. A 2010 study at Newcastle University found hanging posters of faces on the wall prompted people to clean up after themselves more.

But what if the eyes are your own? What if the observer and the observed are one and the same? At first, I thought of Fitbit as a new girlfriend – can't keep away at the start, give up stuff just to be together, and when it all burns out in six to eight weeks, Fitty keeps emailing me (something about "weekly progress reports"), even though I've lost interest. But when I go back to Fitbit with weight maintenance in mind, I begin to think of it differently: an exoskeleton superego, helping me ride herd on the impulses of my id.

Eat carefully, exercise regularly. Basic stuff. But I need help. So I carry Fitbit in my pocket everywhere, or clip it to my gym bag. It's a reminder. It emails me progress reports and Foursquare-like badges (you've climbed as high as a hot air balloon travels, and that's 2,000 floors!). But it's something more. Maybe it is my mirror after all. It only works if I watch it back.

I've always conceived of my life with numbers as a war, so say we've negotiated a demilitarized zone of mutual observation. Except this isn't really a fight anymore. It feels...different.

If I thought the numbers had the capacity for feeling, I'd say we've achieved mutual respect. For a long time, I paid them no attention. But it turns out that was giving them too much power. If I ignored them, they just got bigger, more intimidating. For a long time, I thought they had the path staked out. That it was just a matter of how fast I was going their way. But I might be able to use them to chart my own course. With the help of some tech to navigate.

My scale is still talking to me. Only now, I'm talking back.