The main meaning of the title “The Idea of Ancestry” can be expressed as an interrogative one: Is there an ancestry—an actual relationship to a prior human family—or is it just an idea, a construct of language, photography, and Scripture? The Bible is an ambivalent referent for African Americans, used as it was to help them cope with slavery and other difficulties. Even so, it presents, with its enumeration of the tribes and families of the Hebrew people, the most famous of all Western civilization’s rubrics of homage to ancestry. Meanwhile, it is interesting that Knight does not name the dynastic ancestry celebrated in the Egyptian culture that paralleled the Hebraic one. People of African ancestry can claim an authentic and august pedigree in Egyptian terms, but Knight eschews this. He is without pretension. Instead, he mentions his grandmother five times: She is old, and she has survived long enough to become an ancestor. His grandfathers are both dead. The poem does answer these questions about ancestry, however. Ancestry does exist. The stone wall of the prison dams the poet’s “stream,” his “birthstream.” When it separates him from society, it erases him from history, and therefore he cannot have sons and thus become an ancestor.
The idea of ancestry, therefore, works both ways: The society that put the poet in prison enjoys an ancestry, a historical identity that nourishes and “galvanizes” it. Society denies the dignity of ancestry to the imprisoned poet, whose identity in history is thereby interrupted. Ancestry, however, is collective: “I am all of them” and “they are thee.” Therefore, when society erases the poet’s identity in history by extinguishing his power to have sons, it diminishes the numbers, of which the poet is one, of its ancestral generation and thereby flaws its unanimity. Thus, the space left by the poet’s lost uncle, the space of the prison cell, and “the space between” with which the poem ends represent the loss of personhood, the extinction of freedom, and the end of connection to family, people, and history.