Thanks for the good wishes and other support for my current recovery—knee rehab is going well, if slowly, and I have an excellent pile of books to keep me company.

I’m also reading a posthumous collection of short pieces by David McCullough, the historian, called History Matters. One piece in particular delighted me because it reminded me of a story I’d heard back in high school and forgotten.

The 19th century  Harvard naturalist, Louis Agassiz, set a test for every new student of his. He’d procure an old dead fish from a pail of them. Set it in front of the student, and tell him or her: “look at your fish.”

When he came back to ask the students what they saw, the usual answer was “not much.” Agassiz’s usual response was “look at your fish.”

This might go on for weeks, until the student observed something and was able to articulate what it was. McCullough used the anecdote to illustrate his belief that seeing, looking deeply, is as important to a historian as to a writer.

Much writing advice is made of “show don’t tell,” that hoary proverb. But the essence of being able to show you reader something is to be able to imagine a scene, to see it in full detail, through all the sense. Good writing immerses you, makes you see. The telling is only important as connective tissue for the scenes—the seeing.

This kind of imagination—seeing—takes time and mental effort. And patience. Often we don’t like to slow down. We want our story to flow, to carry us forward on the fastest highway we can manage. But it is in the slowing down—in the looking at your fish—that you can see what needs to be told, what detail will make your readers see.

That slowing down is no fun when you’re hot on the trail of your story, but patience is, as John Dewey said, an expenditure of energy. Before you can make your reader believe your story, you have to make them see. And to make them see, you have to look at your fish: observe, categorize, connect. The fish may be dead, but your story will live.