Page Turner: Steven Johnson's "Invention of Air"

More than 200 years after America's founding, the principal characters and their roles have been largely assigned. But in "The Invention of Air: A Story of Science, Faith, Revolution, and the Birth of America," author Steven Johnson argues that a key player has been all but forgotten. Eighteenth-century English minister, scientist and polymath Joseph Priestley is credited with the discovery of oxygen, but his actual contributions extended into this nation's founding principles.

THE IDEA: Priestley deserves more than just a footnote in high-school textbooks. His insistence that the world was a series of interdependent systems and his refusal to separate the realms of science, faith and politics were embraced by America's Founding Fathers—which speaks volumes about the nation's original values.

THE EVIDENCE: When his home in England was burned by a mob following his takedown of Christianity's more fantastical teachings, Priestley was given a hero's welcome in the new America. Thomas Jefferson credited him with saving his faith. And in the legendary 13-year correspondence between Jefferson and John Adams, Priestley is mentioned 52 times. George Washington gets only three name-checks.

THE CONCLUSION: An expat, a champion of reason, an original progressive—Priestley's ideals were central to the American experiment. He rarely gets the credit, but he was arguably the United States' original advocate for hope and change.