On July 4, 1826, Americans witnessed a seemingly providential coincidence: as the nation commemorated the fiftieth anniversary of the Declaration of Independence, both John Adams and Thomas Jefferson died. Thus ended a fifty-year friendship between a cantankerous New Englander with a realist's skepticism and a conflict-averse Virginian with an optimist's selective vision. The two men first encountered each other in the summer of 1775 as the American Revolution took shape and form. Forged amidst the hardships and risks of war, their friendship was strong, though at times it faced challenges; the bitter partisanship of the 1790s strained it to the breaking point. But in the end, it survived, grounded on each man's fundamental appreciation of the other man's character, and, once the turmoil of public life was behind them, it flourished again. They lived long enough to rekindle their friendship through a rich correspondence, two elder statesmen musing on their lives, their experiences, and the heady events of their times in a written conversation that continued for over a decade. Between 1812 and 1826 Adams and Jefferson exchanged over 150 letters bearing remarkable testimony to their hearts and minds as they reflected on the past, present, and future. Not surprisingly, they often touched on political topics, debating their political differences and ideals, and thinking back on shared allies and enemies and the legacies of their victories and defeats. But their range reached much wider, encompassing topics as diverse as political philosophy, religion, linguistics, and the natural sciences. Their letters have the tone and feel of an ongoing dialogue, the loquacious Adams writing almost twice as many letters as the more reticent Jefferson, but both men clearly reveling in the exchange.