Why does gates consider jefferson the "midwife" of african american literature?

Gates feels that Thomas Jefferson can be aptly named the "midwife" of African American literature because it was he who accused the group of lacking a literature which is symbolic of their civil rights. Thus, in order to prove Jefferson wrong, the blacks began a movement which would lead to the development of a body of literature uniquely theirs. That's why Jefferson can be labeled as a midwife, because he assisted in the birth of African American literature.