A secondhand book sometimes arrives with a stranger's place still in it. A receipt at page 112. A bus transfer. A grocery list with eggs crossed off.

It is the most exact thing you will ever know about that person. Not their name, not why the book left the house — just that they read a hundred and eleven pages, meant to come back, and didn't. A bookmark is a small promise to a future self. This one was boxed up and sold with the promise still inside.

I don't read it as a verdict on the book. People stop for every reason: a move, a baby, a library hold that came in, a winter that got heavy. Page 112 is not where the book failed. It is where life got in.

What I like is what it does to the next reader. For a hundred and eleven pages you are behind someone. Their attention went first and you are walking in it. Then you turn the leaf that held the receipt, and the book changes. As far as you can know, nobody has been here. Every page after is a place they could have gone and didn't.

The obvious move is to throw the receipt out. I would leave it where it is and read past it with my own, until it sits back in the first third like a mile marker.

Shut, the book holds both of you. A slip of paper a third of the way in, and nothing at the end — nobody marks the page they finish on.

A bench in the Rothko Chapel is not there because looking is tiring. It is part of the work.

Fourteen dark paintings surround the room. A quick glance makes them sound simple: black rectangles, repeated. Time disagrees. As eyes adjust, black divides into plum, brown, violet; surfaces refuse to stay flat. Nothing in the room has moved. The bench has only kept the viewer there long enough for the paintings to stop being their description.

Museums often treat seating as an accommodation attached to viewing — useful for older bodies, bored children, tired companions. That gets the hierarchy backward. A room without a seat quietly sets a time limit. It says the work should become legible before knees object, and whatever arrives afterward is optional.

Standing is good for scanning. Sitting permits return. The eye drifts, loses a border, finds it again. Boredom gets a chance to burn off instead of becoming the cue to leave. The body stops announcing itself as an emergency.

I don't want a bench in front of everything. Some work needs collision, not residence. But when duration is part of the medium, seating is not furniture. It is access to the later minutes.

The painting gets the wall. The bench gives it time.

The photograph that settles a race is not a picture of the finish. It is a picture of the finish line, and nothing else, taken over and over.

A photo-finish camera does not see the track. It sees one vertical sliver on the line and records it thousands of times a second, laying each strip beside the last. It looks like a photograph because the eye wants it to be one. Left to right is not distance. It is time. Every runner in the frame is in the same place, at a different moment.

That is why the background smears into horizontal streaks: the grandstand never crosses the line, so it is the same sliver forever. A planted foot stretches long because it stayed on the line while the camera kept scanning. Fast is narrow and slow is wide. A runner who stopped on the line would fill the whole picture.

The Olympic version now scans the line up to forty thousand times a second. At the 2012 US trials, a camera running at three thousand had Allyson Felix and Jeneba Tarmoh crossing in 11.068 seconds each. The rule is the torso, and in the picture from the outside of the track Tarmoh's torso was behind her arm. The timing official offered an estimate from her bib and bicep. The referee refused it — an interpolation is not a fact. Dead heat. A run-off was arranged. Tarmoh withdrew.

The ordinary language is all about proximity. A nose ahead. Neck and neck. Side by side. In the one document that decides, nobody is beside anyone. Each of them reached the only place that counts alone, and the photograph is where they are set next to each other afterwards. A dead heat is not two bodies level. It is two bodies in the same column.