It’s the question that bedevils us all, men and women alike; it’s the question that floats through our minds when we lie awake at night or daydream at our office computers or watch our children at the playground: “Is this all? Is this it?”

It’s the question that unsettles complacency; the question that can, in the right context, topple despots and inspire revolutions. And it’s the question with an equally potentially explosive corollary: “Isn’t there more?”

As I move closer to that comfortably upholstered majlis known as “middle age”, these questions loom large: after all, as one approaches 50, it’s perhaps time to come to terms with the fact that one is not, after all, going to be a ballerina or a fireman; that David Beckham’s career trajectory will not be one’s own.

At 50, one can only hope that “is this all?” returns an answer balanced between satisfaction and aspiration: if 50 is the new 30, maybe we can still finish that novel, learn karate, make an impact on the world in whatever small way is available to us. As that plague victim in “Monty Python and the Holy Grail” protests, “I’m not dead yet … I think I’ll go for a walk this afternoon.”

“Is this all?” is the question that Betty Friedan used in the opening paragraph of The Feminine Mystique, published 50 years ago last week. Her book, which one reviewer described as “pulling the trigger on history,” provided the impetus for feminism’s second wave, the so-called “women’s libbers” who staged protest marches and stormed beauty pageants, who insisted that loading dishwashers and making meatloaf were not the ne plus ultra of the female experience.

Even though Friedan’s book overlooked (or ignored) the very different situations confining women of colour, The Feminine Mystique nevertheless inspired a revolution in the way questions of gender equality were discussed – indeed, in the very fact that gender equality became a subject for public discussion and debate.

Now that the mystique is 50, however, can we turn its question back on itself and ask, “is that all”? How have we handled the gauntlet thrown down by Friedan’s study? In grimmer moments, as when I think about some of the recent encroachments on women’s freedoms in the United States, the epidemic of rape in India and in African countries, the struggle to educate girls in Afghanistan and Pakistan, it seems as if we’re going backwards, that perhaps no society will ever be capacious enough to tolerate the full scope of female autonomy.

I think about my students, male and female, who hail from all the countries of the world and say things like “I’m not a feminist but …” and then conclude their statements with ideas that would be familiar to any 1960s-era women’s libber: that there should be equal pay for equal work, universal day-care, equal access to quality education, and that everyone should have the freedom to marry (or not) whomever they please.

In more optimistic moments, I think that maybe my students’ attitudes reflect the success of the feminist movement: the goals of feminism have embedded themselves in social consciousness, so maybe the refusal of the label “feminist” shouldn’t matter.

And yet, the phrase “feminine mystique” served as the spark that galvanised a revolution. Would that energy have been released without a sense of shared identity, shared purpose, shared anger? Without a common starting point, could people have moved from “is this all?” to “is there more?”

These questions, which seem innocuous enough when we’re asking about extra pudding at dinner, became paving stones on the path that led from what Friedan called “this picture of a half-life” to “a share in the whole of human destiny.” That’s the part of Friedan’s description of feminism that most people miss: it’s not just a “woman thing.” It’s a “people thing”, a reminder that everyone has gender and that none of us, really, want biology to dictate our fate.

Friedan would argue that we still need to ask “is this all”, because too often, all over the world, biology does dictate fate: health, education, opportunity, mortality. Maybe, at 50, The Feminine Mystique still has work to do; maybe this middle-aged lady can still rattle a few cages, can inspire others to ask “is this all?” and “isn’t there more?”

Who knows? Maybe at 50 it’s time for The Feminine Mystique to be translated into Arabic.