I celebrate Labor Day for my grandfathers, one of whom sold hardware to trappers and traders in northern Quebec and the other who worked in sulfur mines of Sicily. Sulfur is the same thing as brimstone, which, as you might recall from the Bible, is an element associated with deep unpleasantness. Is it a surprise that my paternal grandfather headed for Ellis Island? Even the Lower East Side had to be better than hell. We're made from ice, fire and ash — and we're survivors. We're the working class.

My grandmothers did tailoring and piecework in addition to raising hundreds — OK, lots — of children. Don't you think that having eight and nine children, respectively, in days when you boiled diapers, put them through a wringer and pinned them on a line over the air shaft or in a damp tenement basement felt like you were raising the multitudes?

And those multitudes needed to be fed. If you were my grandmothers, you'd be doing the feeding: pea soup for the Tadoussac, Quebec, crowd and pasta with breadcrumbs for the gang in Brooklyn, N.Y. Kids from even poorer families were welcome and, along with everybody else, made a grab when the big bowl of food was passed around.

The idea was for the kids to get jobs and then help out. Both my parents left school after the eighth grade and worked full time. Far more educated than their virtually illiterate mothers and fathers, they wanted my brother and me to surpass them.

They wanted us to get jobs with regular paychecks and regular hours, run by regular people. They wanted us to have the kind of jobs where you took a shower before you left for work rather than as soon as you got home.

Given my heritage, you'll not be surprised that I find the popular adage "Love what you do and you'll never work a day in your life" misleading.

I really like my job, but that doesn't mean that it's play. I have business to transact and, in effect, so do my students. The ones who pass my class take their work as seriously as they'd take any professional assignment. I don't miss class, and neither do my students. I don't show up late, and neither do my students. I submit my work on time and so do my students.

One of the major distinctions between work and play is that attendance is mandatory, according to my Facebook friend Ava Biffer, and that you are required to participate. She's right; even in creative work — writing these columns, for example — there are deadlines and specific requirements. If I don't meet them, watch me be replaced by a recipe for pea soup.

As my Facebook pal Dan Savino suggests, the possibility that our vocations could be the same as our vacations tempts us. But the two words emerge from very different places: "Vacation" comes from the Latin term "vacare," meaning "unoccupied," whereas "vocation" comes from the Latin term "vox," which means voice or calling.

Play is what you do when you're otherwise not occupied. It's why we can play with abandon.

We're called to our work from something outside ourselves, whether it's money, inspiration or the need to be of service. (To paint a house, for example, as my dad painted ours every Labor Day because he had the day "off.") We try to stay within guidelines even if, as we become more skilled and talented, we add occasional flourishes.

Taking pleasure in our occupation does not, however, make it play.

According to former-student-turned-principal Angela Staron, "work has a clear, objective, extrinsic purpose; play has no obligatory requirements." Denise de Ribert adds a distinction between work and play by arguing that work always "involves a boss, client, customer, reader" so that "even if the task is solitary, there is an exchange of labor." In contrast, play can be entirely self-contained since you have no one to please but yourself.

Acknowledging that we must play is another reason Labor Day matters: As Kristine Johnson Mothersele points out, "If you don't work, you don't earn money. If you don't play, you just get sad."

Here's to being happy and productive — and to celebrating Labor Day.

Gina Barreca is an English professor at the University of Connecticut and the author of "If You Lean In, Will Men Just Look Down Your Blouse?" and eight other books. She can be reached at www.ginabarreca.com