Adjunct professors often don’t ‘earn enough to eat.’ The rest of us need to speak up.

I’m a member of an overwhelmingly liberal profession, which routinely decries social and cultural inequities around race, gender, and class. But in its own workplaces, it has also created one of most inequitable systems of labor in the United States.

You guessed it: I’m a college professor.

I’m one of the lucky ones, because I hold a tenure-track position. That means I receive decent wages, retirement benefits, and health insurance. Now that I have tenure, I can also express my opinions — including those in this column — without fear of penalty or dismissal.

» READ MORE: Rutgers strike is suspended, sending faculty back to work with a ‘framework’ for new contracts

Most American faculty members aren’t so fortunate. More than two-thirds of them are so-called adjunct professors, who work on fixed contracts. And many of them make less than $3,500 per course.

I taught adjunct courses, too, when I was in graduate school in the early 1990s. One paid me a grand total of $900, which is about $2,000 adjusted for inflation today.

But that was OK. I was married to a medical resident, who made enough to support us. And I assumed that my low-wage labor would prepare me for a real job — you know, the kind you can actually live on.

I was naïve. Tenure-track positions were already drying up in the mid-1990s, thanks to budget cuts in state legislatures and a glut of Ph.D’s on the job market. Newspapers profiled “freeway fliers,” scholars with doctorates — but without full-time jobs — who drove from campus to campus, teaching multiple classes for negligible pay.

Many of these adjuncts did not receive basic amenities, like an office or a mailbox. Not surprisingly, they spent less time interacting with students than full-time professors did; they were also less likely to assign essays and more likely to use multiple choice tests, which were easier to grade.

Things have only gotten worse since then. Especially in the humanities — including my own field, history — landing a tenure-track job has become something akin to winning the lottery. And the growing number of adjuncts continue to scrape by as best they can. Roughly a quarter of adjunct professors rely on public assistance. Some of them live in their cars; others have turned to sex work to make ends meet.

They can also be let go for the slightest problem, especially if they rub anyone in power the wrong way. In 2017, a New Jersey community college dismissed an African-American adjunct professor after she went on television to defend a Black Lives Matter event that excluded anyone who wasn’t Black. “Institutions of higher learning must provide a safe space for students to explore, discuss, and debate,” the college’s president declared. He said that students, faculty, and their families had expressed “frustration, concern, and even fear” over the professor’s remarks.

But there’s nothing safe about a space where teachers can’t speak their minds or earn enough to eat.

According to University of California at Berkeley Professor David Kirp, adjunct professors are like substitute soldiers who were hired to replace wealthier conscripts during the Civil War. We put them on the firing line, Kirp wrote, and we don’t much care what happens to them after that.

Recently, adjuncts have started to fire back. Dozens of universities have faced strikes in recent years by graduate-student instructors and other adjunct faculty, who are no longer willing to wait for the full-time job that may never come.

Last year, the largest academic strike in U.S. history won raises for 36,000 graduate students at the University of California. And this spring, a grad-student strike at Temple yielded pay hikes and more generous health benefits. It might also have played a role in the resignation of president Jason Wingard, who was widely criticized for his handling of the dispute.

Now comes Rutgers, where the adjunct faculty union struck last week. And so did the union representing full-time professors, who demanded better wages and conditions for the university’s adjuncts as well as for themselves.

The unions suspended the strike on Saturday after reaching a tentative accord with Rutgers, which agreed to a 43% pay increase for the adjuncts. None of that would have happened without professorial solidarity. The tenure-track faculty need to stand up on behalf of their adjunct brethren, whom we have ignored for far too long.

No professor should suffer in poverty and fear, especially at an institution that touts its progressive bona fides. You can shout to the hills about injustice in America. But if you keep quiet about it on your own campus, you’re not a progressive. You’re a hypocrite.

Jonathan Zimmerman teaches education and history at the University of Pennsylvania. He is the author of Whose America? Culture Wars in the Public Schools, which was published last year in a revised 20th-anniversary edition by the University of Chicago Press.