Fleeting encounters

I planned to use lightroom's face-recognition feature to organize my personal photos. But then all these other faces popped up. Tiny, in the background of other photographs, often out of focus, in movement or underexposed. This is people that I have briefly seen, exchanged a glance with, maybe even a smile. But what remains of these encounters, other than on the sensor of the camera, what effect does all the people we see everyday have on us. So I looked through my archive, about 50.000 photos, and enlarged the faces that intrigued me the most.