What, then, will people do when they retire? I asked Ghilarducci. “Their retirement plan is faith based,” she replied. “They have faith that it will somehow work out.”

I laughed, but it’s not funny. “The 401(k),” she concluded, “is a failed experiment. It is time to rethink it.”

In truth, I’m one of the lucky ones. I do work that I love, which requires no heavy lifting and has no mandatory retirement age. If I become incapacitated, I will have assisted-living insurance. Otherwise, I can keep writing till I drop.

But, for the millions of others who have discovered, as I have, that their original enthusiasm for investing was unwarranted, their faith-based retirement plan is all they’ve got left.