Why is harmony important in life?

While some men are as bad as firebrands thrown in our midst, others, calm and self-possessed, sway with mildness and gentleness the wills they come in contact with—not seeking to bring all into their way of thinking, but after stating their individual opinions, leaving to their opponents the privilege of doing as they, in their individuality, think right. 

And how often do you find that they have convinced without effort and harmonised while they have convinced.

—L. D. in Spirit