In he poem "Stanzas on Freedom" written by James Russell Lowell

Probably someone who was complascent about slavery.

He's talking about every type of person from slave to landowner, to women, to children; he wants people to see the importance of freedom and the atrocity that was slavery.

Probably someone who was complacent about slavery. I think he wanted them to speak up about injustice even though they may not be directly affected by slavery. He wants people to realize that we are all brothers and sisters and that one abuse affects all of us.