Frederick Douglass is a name you may have to search for in your high-school memory.
A short tutorial in case you don't find him lurking behind your other must-remember files: kids birthdays, dry cleaning pick-up, dentist appointment re-schedule, conference paper submission, etc, ad nausuem-adult-responsibility-can't forgets.
As a young man, Douglass escaped slavery to become one of, if not the most eloquent, intelligent, spokesman against slavery. His use of language, both in his oratory and in his writings, led the people of the time to question if he really had been a slave. His abilities were proof against slaveholder beliefs clung to like a log in a raging river: all men were not created equal.
Douglass was a prolific writer most famous for his autobiography, but most of his writing focused on his logic and reason for emancipation; but for all his argument, his most enlightened angle is a universal truth that held weight not only in the 19th century and every hundred years before, but for every hundred years after.
I once wrote that I'd rather my child be bullied than my child be the bully--because the bully is far more injured than any injury he could inflict on a victim, and the taunting more injurious to the bully than the bullied.
Replete through Douglass' writings is this theme. Not only must slavery be stopped for slaves but for the salvation and mercy of slaveholders.
In Douglass' Oration in Memory of Abraham Lincoln (1876, eleven years after the Civil War), he writes,
"I refer to the past not in malice, for this is no day for malice; but simply to place more distinctly in front the gratifying and glorious change which has come both to our white fellow-citizens and ourselves, and to congratulate all upon the contrast between now and then; the new dispensation of freedom with its thousand blessings to both races, and the old dispensation of slavery with its ten thousand evils to both races--white and black."
The unjust treatment of anyone or anything cannot escape without impunity. One cannot look in the mirror without it looking back. Everything is a reflection of our actions and who we are. Douglass' writings are replete with this message: slavery hurts slaveholders and the nation, as much as it hurt slaves. Slavery is contrary to the law of nature. "The law of nature requires that we should endeavor to help one another to the utmost of our power in all cases where our assistance is necessary. It is our duty to endeavor always to promote the general good; to do to all as we would be willing to be done by were we in their circumstances; to do justly, to love mercy, and to walk humbly before God" (Samuel West, 1776). Slavery disregarded the Golden Rule.
If we want to be happy, bring happiness to others. If we want to feel peace, let peace rain in your presence. If we want our souls to be nourished, nourish souls with love and kindness.
Actions are a boomerang. Always.