For countless other jobs that once required little or no formal academic training—preschool teacher, medical technician, dental hygienist, physical-therapy assistant, police officer, para­legal, librarian, auditor, surveyor, software engineer, financial manager, sales manager, and on and on—employers now look for a degree. In some of these instances, in some jurisdictions, the law requires one. All of these occupations are, or soon will be, closed to nongraduates. At the very least, some of the public and private investment in additional education needs to be questioned.

To be sure, today’s IT-driven world is creating a genuine need for some kinds of better-educated workers. It is the shortage of such people, according to most politicians and many economists, that is causing the well-documented rise in income inequality. Both to spur the economy and to lessen inequality, they argue, the supply of college graduates needs to keep rising.

It seems plausible, but this theory too is often overstated, and does not fit the facts particularly well. The college wage premium rose rapidly for many years, up to the late 1990s. Since then it has flattened off, just when the pace of innovation would have led you to expect a further acceleration. An even more awkward fact is that especially in the past decade or so, rising inequality has been driven by huge income increases at the very top of the distribution. In the wide middle, where differences in educational attainment ought to count, changes in relative earnings have been far more subdued. During the 1990s, CEO salaries roughly doubled in inflation-adjusted terms. But median pay actually went up more slowly than pay at the bottom of the earnings distribution, and even pay at the 90th percentile (highly educated workers, mostly, but not CEOs) increased only a little faster than median wages. Today, shortages of narrowly defined skills are apparent in specific industries or parts of industries—but simply pushing more students through any kind of college seems a poorly judged response.

The country will continue to need cadres of highly trained specialists in an array of technical fields. In many cases, of course, the best place to learn the necessary skills will be a university. For many and perhaps most of us, however, university education is not mainly for acquiring directly marketable skills that raise the nation’s productivity. It is for securing a higher ranking in the labor market, and for cultural and intellectual enrichment. Summed across society, the first of those purposes cancels out. The second does not. That is why enlightenment, not productivity, is the chief social justification for four years at college.

Shoving ever more people from high school to college is not only of dubious economic value, it is unlikely to serve the cause of intellectual enrichment if the new students are reluctant or disinclined. Yet there are still large prizes to be had through educational reform—certainly in enlightenment and perhaps in productivity. They simply lurk farther down the educational ladder.

The most valuable attribute for young people now entering the workforce is adaptability. This generation must equip itself to change jobs readily, and the ability to retrain, whether on the job or away from the job, will be crucial. The necessary intellectual assets are acquired long before college, or not at all. Aside from self-discipline and the capacity to concentrate, they are preeminently the core-curriculum skills of literacy and numeracy.

Illiteracy has always cut people off from the possibility of a prosperous life, from the consolations of culture, and from full civic engagement. In the future, as horizons broaden for everybody else, people lacking these most basic skills will seem even more imprisoned. The most recent National Assessment of Adult Literacy found that 30 million adult Americans have less than basic literacy (meaning, for instance, that they find it difficult to read mail, or address an envelope). Three out of ten seniors in public high schools still fail to reach the basic-literacy standard. Progress on literacy would bring great material benefits, of course, for the people concerned and some benefits for the wider economy—but those benefits are not the main reason to make confronting illiteracy the country’s highest educational priority.

In addressing the nation’s assorted economic anxieties—over rising inequality, the stagnation of middle-class incomes, and the fading American dream of economic opportunity—educa­tion is not the longed-for cure-all. Nor is anything else. The debate about these issues will have to range all across the more bitterly disputed terrains of public policy—taxes, public spending, health care, and more. It is a pity, but in the end a consensus that blinds itself to the complexity of the issues is no use to anyone.