According to Adam Smith’s The Theory of Moral Sentiments 
So long as disagreements and divergence of sentiment focus on minor topics, they are tolerable: “I can much more easily overlook the want of this correspondence of sentiments with regard to such indifferent objects as concern neither me nor my companion, than with regard to what interests me so much as the misfortune that has befallen me, or the injury that has been done me. Though you despise that picture, or that poem, or even that system of philosophy, which I admire, there is little danger of our quarrelling upon that account. Neither of us can reasonably be much interested about them. They ought all of them to be matters of great indifference to us both; so that, though our opinions may be opposite, our affections may still be very nearly the same.”
But when two people have different sentiments about things that are of great moment to them, sparks fly:
“But it is quite otherwise with regard to those objects by which either you or I are particularly affected . . . . We become intolerable to one another. I can neither support your company, nor you mine. You are confounded at my violence and passion, and I am enraged at your cold insensibility and want of feeling.” One wonders if Smith, like many of his era, is thinking of religious sentiments.
In order to overcome this quarrel and attain a degree of harmony, each party must take a position of distance, adopt the stance of a spectator: “In order to produce this concord, as nature teaches the spectators to assume the circumstances of the person principally concerned, so she teaches this last in some measure to assume those of the spectators. As they are continually placing themselves in his situation, and thence conceiving emotions similar to what he feels; so he is as constantly placing himself in theirs, and thence conceiving some degree of that coolness about his own fortune, with which he is sensible that they will view it.”
There is a double movement here. The person who is indifferent to the subject has to enter imaginatively into the sentiments of the “person principally concerned” and the latter must “bring down his emotions to what the spectator can go along with.” This imaginative act demands “two different sets of virtues. The soft, the gentle, the amiable virtues, the virtues of candid condescension and indulgent humanity, are founded upon the one: the great, the awful and respectable, the virtues of self-denial, of self-government, of that command of the passions which subjects all the movements of our nature to what our own dignity and honour, and the propriety of our own conduct require, take their origin from the other.”
This is an act of imaginative sympathy: If I can put myself in the other’s position and see as he sees it, I can attain a degree of sympathy with his opinion. Imagination lends a degree of equilibrium to my viewpoint. Concord is built on sympathy, and sympathy on imagination. Imagination depends on virtues of amiability and self-control. without virtue, no imagination. And, an unimaginative society will, by Smith’s lights, be an unsympathetic and quarrelsome one.