The observer's paradox states that the nature of an occurrence changes by virtue of it being observed. That by looking, you inadvertently alter.
Picture: sallow faces huddled in alleys.
Has something been lost? Has something been gained?
Or has something simply changed?
Imagine: a young man walks the streets, catches sight of the poor and thinks their suffering is art; for art doesn't have to be beautiful, it just has to make you feel.
Imagine: "Young ladies, please step to the right, your skirts are too bright for this scene."
And, "Dear, could you hunch? Gentlemen, step back, your hats are blocking the door."
Or, "That's it, turn towards the wall and sink to the ground. Use that cloth to hide your faces."
But it's fine. It's only a painting—they gain money from him, after all.
Perhaps: a desire for detail;
"It won't take much of your time. Just leave the queue and come with me. I'll make it worth your while."
Then: "Sit as you had in the alley, angle your head so you gaze at the floor."
The observer, of course, gets to walk away.
The subject remains unchanged.
"There's a problem with the composition—Madam, clutch your child, hold his hand. Think poverty, think destitution. Someone move that dog; no, wait, leave it there. Lady, wait until the outline is done.
You in the middle, arch your back; think of long winters with no food."
Picture: "Yes! That's it! Now, stay as you are. No, wait, I want greater desperation. No, I mean, a little less agony and maybe a little more misery."
And something, somewhere, is lost.