Jonah Goldberg, the columnist and conservative intellectual, recently published an essay about America’s complicated relationship with freedom. Writing in The Dispatch, he argued that most Americans are libertarian only when it comes to freedoms they personally prize and are often content to let government regulate or prohibit freedoms they don’t value — or don’t want others to have. This selective consistency feeds today’s partisan hypocrisy, with both left and right defending liberty or state intrusion depending on who’s in power.

From there he built to a larger point — that beneath the rivalry between red and blue, America’s real exceptionalism lies in its culture: a deeply ingrained instinct for individual rights, autonomy, and resistance to government meddling. That common instinct, which Goldberg calls “American groundwater,” runs deeper than our politics, and those politics would be healthier if more of us could train ourselves to see fellow Americans — even those with opposing views — as part of the same liberty-valuing culture.

I bring up Goldberg’s essay not only to recommend it but also because I was struck by the question with which he introduced it: “What principle do you hold,” he challenged his readers, “that is against your self-interest or political desires?”

It’s a cogent and revealing test. It obliges anyone who answers the question to think about whether they embrace their convictions for their truth or merely because they’re convenient. Anyone can defend the freedoms or prohibitions that serve their own purposes. The truer test of ideological and moral seriousness is whether you adhere to your principles even when doing so cuts against your interests, tastes, or partisan loyalties.

This isn’t an ivory-tower abstraction. American history is rich with examples of people who upheld principle at real personal cost. John Adams, though a patriot who hated British rule, risked his career to defend the redcoats accused in the Boston Massacre, convinced that even despised defendants deserved counsel and a fair trial. Justice John Marshall Harlan, raised in a Kentucky family of enslavers, broke with his social milieu to insist in his lone dissent in Plessy v. Ferguson (1896) that “our Constitution is color-blind.” And in 1960, Richard Nixon, urged by allies to contest an election marred by serious irregularities, refused to plunge the nation into turmoil, saying the country’s stability mattered more than his own ambition.

I have tried to meet that test in my own writing — with what success, I leave others to judge. For instance, I defend the right even of Holocaust-deniers to spread hateful and repellent lies, because freedom of speech is not just for ideas I share. I have criticized political figures I admire when they promoted foolish policies — and stood up for political figures I dislike when they were attacked unfairly. In a column about freedom of association, I defended the right of both a web-hosting company to refuse service to a racist group and a gym to refuse service to police officers and military personnel. The first call was easy, the second less so, but in both cases the principle was the same: Private businesses should be allowed to decide with whom they will (and won’t) do business.

I have sometimes put a version of Goldberg’s question to candidates in a primary election: Can you name a position you take that is clearly opposed by most of your party’s base? Rarely have I gotten a substantive answer. Most politicians duck the question, unwilling to announce that they uphold an unpopular position on principle — even though doing so would be pretty strong evidence that their convictions were genuine.

What makes this problem worse is the increasingly common belief that only those who agree with us are legitimate participants in American life. Too many on the right write off their opponents as anti-American, while too many on the left see theirs as irredeemably bigoted or authoritarian. If you begin from the premise that dissenters are not merely wrong but illegitimate, then there is no reason to extend to them the rights or freedoms you claim for yourself.

But that mind-set drains principle of all meaning. Defending free speech only for your allies is like championing religious liberty only for your own faith: That’s not upholding a principle — it’s wielding a partisan cudgel, something that has become endemic in contemporary American life. So much of what bedevils our civic discourse these days, Goldberg writes, begins with “the premise that America is defined by our politics and, therefore, the people with the wrong politics are not Americans.”

Which is why Goldberg’s challenge ought to be posed more often. A principle that only applies when it’s easy isn’t much of a principle at all. So, readers, I’ll put the same question to you: What principle do you hold that runs against your own interest or desire? Please give it some thought and share your reflections. In a future column, I’ll share some of the more intriguing and noteworthy responses.