Discussed in this essay:

The Life of Saul Bellow: To Fame and Fortune, 1915–1964, by Zachary Leader. Knopf. 832 pages. $40.
There Is Simply Too Much to Think About: Collected Nonfiction by Saul Bellow, edited by Benjamin Taylor. Viking. 608 pages. $35.

Definitive” is the highest praise for a biographer, the only adjective worth aspiring to. Yet nothing is harder to define, more essentially unknowable, than the life of another human being, with all its ambiguities and knowledge gaps — the “epistemological insecurity” about which Janet Malcolm, one of the most trenchant critics…