In a postscript to a study published two years ago, a Harvard sociologist says that from "5 to 20 per cent of the [American] black population (from 1 to 4 million people) hold attitudes indicating a depth of estrangement and bitterness unique in American history."
The sociologist-Gary T. Marx, assistant professor of Social Relations-says that the bitterness is growing noticably among younger blacks and among those living in the North. Marx's comments came this week in a 27-page addition to his earlier work, "Protest and Prejudice: A Study of Belief in the Black Community."
He reports "a marked disparity between blacks and whites... with respect to ideas about the treatment of blacks, integrated schools and housing, the cause, meaning and consequences of riots, and the type of ameliorative action required."
This disparity, he says, "indicates a profound lack of communication and the absence of understanding or compassion among a very large portion of white public."