Not long ago I had an experience that most authors wish for. Someone recommended my book.

A librarian at the Toronto Public Library had included my book on a list, along with five others, in celebration of International Day of Persons With Disabilities. Two of the other authors have autism, one is deaf, one was born without legs, and the fifth, a woman who has cerebral palsy, endured a 16-month escape from her native Syria in a wheelchair. I should have felt proud to be in their company. I should have sent the link to my parents, as I’ve done with other lists my book has made. But I didn’t. I felt confused.

I don’t think of myself as disabled. Twenty-three years ago, when I was a junior at Harvard, a boy’s finger hooked into my right eye during a basketball game, shearing my optic nerve from the back of my eyeball. Without an intact optic nerve, my right eye cannot relay information to my brain. As someone blind in one eye, I qualify as a person with a disability under the Americans With Disabilities Act, but I can also drive and play sports, and my cognitive abilities have not changed. To consider myself a person with a disability doesn’t seem right, especially compared with the other authors on the library’s list.

And yet, I also don’t think of myself as the opposite of disabled — whatever the word for that is. Depth perception depends on binocular vision: The brain needs information from both eyes to coordinate where objects are in space. Without depth perception, I often stumble on stairs and curbs, and sudden drop-offs, like sunken living rooms, greet me with a jolt. I also have no peripheral vision on my right-hand side, so I try to position myself on the right in meetings, in restaurants, and when walking with friends. I rely on my hearing, which has become almost painfully acute since my eye accident, to negotiate busy sidewalks. Even so, with a blind spot on my right side larger than my brain remembers, I often crash in crowds.

All of which puts me in what box? Half-disabled? Being privileged enough not to need special accommodations, I hadn’t needed to ask myself that question. And in my one friendship with someone else with monocular vision, the question never came up. But other questions did, and they were crucial in shaping my perspective. The friendship was with the neurologist Oliver Sacks.