When George Wythe died in 1806, he left his small library of books to his dear friend and former pupil Thomas Jefferson. It was, he wrote in his will, “the most valuable to him of anything which I have power to bestow.”

Yet Wythe’s greatest gift to Jefferson—and to the new United States of America—had already been given, and was on display for the world to see in the Declaration of Independence. The things we celebrate on our nation’s 250th anniversary—those self-evidence truths and those foundational principles—can be traced to Wythe’s intellect and influence.

George Wythe was the man behind the man behind the Declaration of Independence. And his most important lesson—that civic virtue must be cultivated—is something that must be learned anew, with each generation.

Not many of Wythe’s words have survived him, but in just one example, the principle of “no taxation without representation” was first argued in this context by Wythe himself in 1763, when he joined Patrick Henry in fighting the now-infamous Stamp Act: “The laws imposing taxes on people, ought not to be made without the consent of representatives chosen by themselves,” he wrote.

Sound familiar? One of the outrages Jefferson later listed in the Declaration was that King George III was “imposing taxes on us without our consent.”

Wythe was a signer of that document, fully cognizant that signers were risking “our lives, our fortunes and our sacred honor.”

But Wythe’s real contribution to the revolution had been made much earlier. For three of his most formative years, Jefferson sat at Wythe’s table, learning the law—and much more. Wythe became Jefferson’s “second father.”

“He was my ancient master, my earliest and best friend, and to him I am indebted for first impressions which have had the most salutary influence on the course of my life,” Jefferson wrote.

Wythe planted seeds in young Jefferson that would form deep roots.

“Jefferson’s lessons extended far beyond matters of law,” writes Clemson University’s Samuel Postell. “Though Jefferson dutifully studied Coke on Littleton and purchased volumes on pleading and statutory law, Wythe also directed him toward works on history, literature, philosophy, religion, and science. Jefferson later advised aspiring lawyers to study science, ethics, and religion before breakfast, devote morning hours to law, and spend afternoons and evenings on history and literature, the same schedule that Wythe suggested for his pupil.”

Some of his contemporaries (including that firebrand, Patrick Henry) considered him too “nice” to be an effective combatant in Constitutional Congress’ most bruising political debates.

Perhaps they were right, but Wythe’s genius wasn’t in raucous debate; it was in his conviction that good statesman should first be good citizens—and good people.

“Wythe understood that character and the proper education were the necessary foundation for the founding of America’s institutions, self-government, and law-making,” Postell notes. “Monarchy relies on the virtue of one, aristocracy on the virtue of a few, but a republic demands widespread civic virtue. Civic virtue must be cultivated; it cannot be inherited.”

That’s certainly true today, even as we face what Arthur Brooks calls “a crisis in civic virtue.”

“The problem for democracy today is not capitalism; it is a decline in public honesty and civility, which are necessary to govern free markets and are also central to a democratic society,” Brooks wrote recently.

According to Jefferson, Wythe embodied those civic virtues.

“No man ever left behind him a character more venerated than G. Wythe,” Jefferson wrote. “His virtue was of the purest tint; his integrity inflexible, and his justice exact; … a more disinterested person never lived. … and his unaffected modesty and suavity of manners endeared him to every one.”

Later, a young James Madison also came to learn the law at the table of Mr. Wythe; in that way, Wythe also became the grandfather of the U.S. Constitution.

What’s unique about our American holiday is that it celebrates not a momentous military victory, but rather a victory of ideas. George Wythe ensured that those ideas were baked into the very founding of our nation.