The U.S. Capitol before sunrise on Friday. (Andrew Harrer/Bloomberg News)

Welcome back to The Monkey Cage’s weekly presentation of Founding Principles, a series of short videos designed to explain American government and how it works — in theory and in practice.

The first five episodes looked at the basic structure of the government created by the U.S. Constitution — the separation of powers between its levels and across its branches, and then at each of those branches in turn: Congress, the presidency and the judiciary.

Now we’re ready to turn to the ways that “we, the people,” interact with that government. Over the next five episodes we’ll look at the role of public opinion and the media, see how elections work, and examine ways other than voting by which people can participate in politics.

Public opinion is a fundamental place to start. After all, as William McKinley put it, “Here the people rule, and their will is the supreme law.” But the framers of the Constitution were nervous about turning unfiltered public opinion into public policy. As James Madison wrote in Federalist #55, “Had every Athenian citizen been a Socrates,” he said, “every Athenian assembly would still have been a mob.”

And how do we know what the people actually want, anyway? The past few years have seen plenty of polling controversies. Tabulating public opinion accurately faces many challenges. Worse, do people know enough about government to have reasonable opinions? A well-known political science book, “What Americans Know About Politics and Why It Matters,” effectively concluded that the answer to the first half of its title was: Not much.

Luckily, even though individuals can certainly be irrational — or simply lack knowledge about political events — many scholars believe in something called a “rational public.” It is possible, as the framers knew, to rest our government on a “due dependence on the people.” And to conduct an accurate poll. This episode helps show how.