What unites us? Dan Rather visits Boston.

The voice of reason and hope visited Boston last Thursday, in the form of 86-year old journalist Dan Rather.

When things seem particularly dire, it’s always good to turn to your elders for a dose of perspective.

Dan Rather by Ben Baker/Redux

The evening I saw Dan Rather speak at Berklee College was at the end of another bewildering and horrible day for America. It was the same day that Trump made his “shithole countries” remark in front of several senators during a discussion in the Oval Office on immigration reform. At the end of that shithole day, Dan Rather was onstage looking dapper and being interviewed by WBUR’s Anthony Brooks about his new book, What Unites Us.

Mr. Rather looks to history to divine our nation’s possible future. Spoiler alert: he is optimistic about our chances to survive the Trump presidency, but only if we focus on what unites us as a nation.

Such as…? Literacy and reason. Our Founding Fathers personify the Age of Reason—the Enlightenment. It’s an American tradition to explore and test new ideas, based in critical thinking and fierce debate.

Rather points to centuries of examples to make his point that patriotism wielded as a “cudgel” in arrogance and divisiveness, especially in a multi-ethnic state such as ours, could lead to tribalism. The inference was clear: the unchecked rise of authoritarianism and nationalism could mark the end of our democratic institutions and the freedoms that we hold dear, but all too often take for granted.

Patriotism is a very personal thing, said Rather. “It is a deep and abiding love of country.” But, he added, humility is the necessary trait that most differentiates patriotism from nationalism.

Dissenters—be they Revolutionary War patriots or women in knitted pink pussy hats—point to the truth. This defense of the truth, and of our liberty to speak it, is what makes America great.

Rather writes: “And in moments like the present, when our government has become erratic and threatens our constitutional principles, dissent is doubly necessary to resist a slide into greater autocracy.”

While dissent can divide us, it can also be what unites us.