
This picture may not in fact detain you for more than a minute. All you see are two old people, awkwardly lit and framed and poorly focused, the composition tilted from presumed ineptitude rather than adherence to Constructivist principles. But! Here I will buttonhole you. Notice how the composition is tilted in order to set her upright--she is the center of power and deserves nothing less. Notice how the picture depicts a moment that can stand metonymically for the whole course of a long relationship. After all these years he is still trying to sweet-talk her--he may be making excuses, or reciting poetry--as she continues to reserve judgment. Notice how beautiful they both are, and how you can see their younger selves still burning within. Notice his galluses and sleeve-garters. Notice the shallow space, the underlighting, the wallpaper, the matching chairs, the radio. Notice how the tilting and the underlighting and the shadows and the disarray in the foreground make the picture look satirically scandalous, even give it a bit of a true-crime aura. Notice how the picture embodies what you may not previously have thought of as romance.
I have confidence in my eye. So do John and Mary, presumably. If we were disagreeing about Bordeaux vintages or minor Augustan poets or alternate takes of "Koko," we could each cite authorities to back us up, could refer to a history of opinions, could generally act as though there was such a thing as an objectively correct view. You can't do that with snapshots, and you never will be able to do so. The snapshot forces everyone who sees it to make an authority-free decision, and--if an explanation is sought--forces everyone to become a critic, in the best sense of that word. Everyone who looks at a snapshot can become an exemplary critic, one who doesn't generate pull-quotes or ritually invoke upper-case names or rely on a mess of filters. Historically, the snapshot was a great equalizer, allowing people of all classes to make pictures, and once again it is a great equalizer, forcing everyone to think for themselves.
Many thanks to Annie Nocenti for the pic.