For proponents of capitalizing black, there are grammatical reasons — it is a proper noun, referring to a specific group of people with a shared political identity, shaped by colonialism and slavery.

Vilna Bashi Treitler, a professor of black studies at the University of California, Santa Barbara, said that racial categories were fabricated, created to denigrate people considered to be nonwhite.

Black and white are adjectives, not proper nouns to be capitalized, she said, calling a term like “African descendant” a more appropriate way to characterize black people.

“It’s a placeholder for describing the group of people who are perpetually reinserted into the bottom of the racial hierarchy,” Dr. Bashi Treitler, the author of the book “The Ethnic Project,” said of the term black.

Now Dr. Fleming, a professor at the State University of New York at Stony Brook and the author of “How to be Less Stupid About Race,” is writing a book for young people about fighting racism.