from a letter from Saul Bellow to Arno Karlen on 8/17/61 that is in this week's New Yorker:
Everyone is writing "Ulysses" all day long, within himself, and when we speak we speak sentences out of an inward context - only the tip of the iceberg appearing above the surface. So that you heard only the clause beginning with "but," and not what preceded it.
What I should have said to you about being a writer would have gone something like this: One has the choice now of coming before the world as a writer or actually being one. The Mailers and the Angries are dissatisfied with what you call the rapping on the cell wall, and they have decided to make a public appearance in the writer's role.