There is a consensus among poverty experts that over the past 50 years there has been some improvement in the condition of the poor.

“Anyone who studies the issue seriously understands that material poverty has continued to fall in the U.S. in recent decades, primarily due to the success of anti-poverty programs” and the declining cost of “food, air-conditioning, communications, transportation, and entertainment,” David Autor, a professor of economics at M.I.T., wrote in response to my query.

Despite the rising optimism, there are disagreements over how many poor people there are and the conditions they live under. There are also questions about the problem of relative poverty, what we are now calling inequality. Poverty cannot be viewed in isolation from the larger economy. We must take disparities in the way the benefits of growth and productivity are distributed into account.

I set out to ask a number of experts about this in response to a controversial essay published in the current issue of the New York Review of Books, “The War on Poverty: Was It Lost?” by Christopher Jencks, a sociologist at Harvard with unassailable liberal credentials.