On Saturday, some 1,500 students from all over the world gathered to discuss freedom at the Students for Liberty Conference in Washington, D.C.

Economist Donald Boudreaux showed the students a department store catalog from 1958 to underscore how the free market, while contributing to income inequality, also dramatically improved the lives of the poor: "The typical American worker back then had to work 30 hours to buy this vacuum cleaner. Today, a worker has to work only six hours to buy a much better vacuum cleaner. And that's true for clothing, food, all sorts of things."

That's how free markets work: quietly, gradually improving things. That doesn't always appeal to impatient young people — or to radical old people who fancy themselves social engineers who should shape the world.

Such social engineering is revered on campuses. A student from Quebec complained that economists about whom his fellow students learn are "Keynesians, who believe that breaking windows is good for the economy, or neoclassicals, who believe in unrealistic assumptions like perfect competition and perfect information."

If there were a part of America for which the American students at this conference felt a special pride, it was the Constitution.

"The Constitution of the United States is a promise about how government power will be used," Timothy Sandefur, author of "The Conscience of the Constitution," told them. "A promise was left to us by a generation who lived under tyrannical government and decided they needed a framework that would preserve the blessings of liberty."

These students appreciated that inheritance, although they said the Constitution is rarely discussed at their schools. They surprised me by knowing the correct answer to my question: How often is the word "democracy" used in the Constitution?

Answer: never. The founders understood that democracy may bring mob rule — tyranny of a majority. So the Constitution focuses on restricting government — to secure individual liberty.

If anything, these students were stauncher in their defense of liberty than the Founders.

Kelly Kidwell, a sophomore from Tulane University, said, "Regardless of what its intent was, we still have the (big) government that we have now — so the Constitution has either provided for that government, or failed to prevent it."

That's an argument that libertarian economist Murray Rothbard used to make. He took the pessimistic view that the Constitution's "limited government" was an experiment that had already failed, since 200 years later, government was barely limited at all. He concluded that libertarians should be not just constitutionalists but anarchists — get rid of government completely.

That idea sounds extreme to me, and to some libertarians at the conference — not to mention the few pro-big-government speakers, like movie director Oliver Stone. But I'm happy that students ask those sorts of questions rather than wondering which regulations to pass, what to tax and whom to censor for "insensitive" speech.

Even in an audience filled with libertarians, there were unsettled issues and divisive questions. Some students and speakers sounded a lot like the campus leftists who complain about "privilege." Others sounded conservative and sought guidance from their religion.

I think this diversity is a good sign for the future of libertarian ideas. There are many ways for free people to live and to accomplish their goals — and as these students learned, the most important thing is not to assume that government has the answer to the questions.

Students for Liberty's website says: " . . . this is the most libertarian generation. The millennial generation is more social, organized, and receptive to liberty, but also the most punished by the economic misconduct of older generations."

Old politicians and old voters may never change their minds. But libertarianism grows fastest among the young, and so groups like Students for Liberty give me hope. Those young people sure know more about liberty that I did when I was their age.