The aftermath of President Obama's meeting yesterday with the GOP leadership sparked a discussion that recurs with some regularity within conservative circles. (President Obama pronounced the meeting “extremely civil,” and Republicans concurred.)

The argument is sometimes made, directly or obliquely, that civility is merely a guise, the first step toward bipartisan compromises that betray conservative principles. And at times there is something to this critique. Civility has been used as a cover for hollowed-out principles, for lukewarm philosophical commitments, and for those who believe in nothing and are willing to fight for nothing. I get all that.

But civility need not be any of this, and it's important from time to time to remind ourselves why it's quite important to our political and civic life. It's therefore worth correcting some interpretations that, like barnacles that attach themselves to the hull of a ship, associate themselves with the concept of civility.

Civility is not a synonym for lack of principles or lack of passion. They are entirely separate categories. Civility has to do with basic good manners and courtesy, the respect we owe others as fellow citizens and fellow human beings. It is both an animating spirit and a mode of discourse. It establishes limits so we don't treat opponents as enemies. And it helps inoculate us against one of the unrelenting temptations in politics (and in life more broadly), which is to demonize and dehumanize those who hold views different from our own.

We can possess civility while at the same time holding (and championing) deep moral and philosophical commitments. In fact civility, properly understood, advances rigorous arguments, for a simple reason: it forecloses ad hominem attacks, which is the refuge of sloppy, undisciplined minds. “Before impugning an opponent's motives,” the philosopher Sidney Hook once said, “even when they may rightly be impugned, answer his arguments.”

Here a few caveats are in order. Civility does not preclude spirited debate or confrontation. Clashing arguments are often clarifying arguments. Civility does not mean we do not call things by their rightful name. Evil is sometimes evil; and wicked men are sometimes wicked men. Nor does civility mean splitting the difference on every issue under the sun. (Who was right — eight clergymen in Alabama who said civil rights activism was “unwise and untimely” or the young minister sitting in a Birmingham city jail who told these “white moderates” that they preferred “a negative peace which is the absence of tension to a positive peace which is the presence of justice”?) I would add that the most important debates and many of the most important figures in American history were polarizing. They stirred deep passions in people, which is precisely when civility and even a measure of grace are most needed, to keep democratic discourse from jumping the rails.

In all this, Abraham Lincoln is, as he almost always is, a model. Lincoln is the finest political writer and, with James Madison, the finest political thinker in American history. He set a standard for meticulous, sophisticated arguments that had never been seen and has never been matched. As a young man, it is said, his satirical inclination and self-confident polemical power provided him with the “power to hurt.” But as he matured, William Lee Miller has written, “one can almost observe him curbing that inclination and becoming scrupulous and respectful.” His personal and professional dealings — with clients, editors, supporters, and opponents — had a “distinctive quality of tact, generosity, and civility.”

In response to a visit by citizens after the 1864 election, Lincoln said, “So long as I have been here I have not willingly planted a thorn in any man's bosom.”

None of us possesses Lincoln's virtues. But all of us should aspire to cultivate them.

Peter Wehner is a senior fellow at the Ethics and Public Policy Center in Washington, D.C. He served in the Bush White House as director of the office of strategic initiatives.