I recently shared some statistics from Charles Murray’s book Coming Apart that illustrate some of the fundamental social and cultural changes that occurred in America during the last half-century.

One fascinating bit of data I did not share touches on U.S. poverty levels, as well as American perceptions of poverty.

In 1963, roughly 20 percent of Americans lived below the poverty line. (Today, by comparison, the poverty rate stands at 13.5 percent, according to U.S. Census Bureau data.)

However, Murray points out that a Gallup poll taken that fall showed that 95 percent of Americans identified as either middle class or working class. The poll reveals many poor Americans were refusing to identify as such, just as many affluent Americans were refusing to define themselves as upper class.

This reminded me of a story my grandfather told me many years ago.

Born into a large family in Wisconsin at the onset of the Great Depression, his family had very little money. Once, when some of the neighborhood children were going to the dime store, he asked his father for a penny to get a piece of candy. His father left, and returned a minute or two later. He was empty-handed.

“I’m sorry, son,” he said, spreading his hands in what might have been mild embarrassment. “I don’t have a penny to give you.”

What my grandfather told me next is something I will always remember.

“The funny thing was, not once growing up did I ever think of us as poor,” he said. “That was just how it was, for us and everybody.”

I didn’t know it at the time, but my grandfather was sharing with me an integral truth about America, something Murray describes as “a national conceit” that had prevailed since America’s founding:

“America didn’t have classes, or, to the extent that it did, Americans should act as if we didn’t.”

Needless to say, this is no longer the case. Not only has America become divided into distinct classes—dangerously so, according to Brookings scholar Richard Reeves—we’ve become hyper-aware of class.

Understanding how and why it’s happening is a central theme of Murray’s book.