Answer:
Keeping slaves clearly causes their slaveholders to become power blind and thereby bring inhuman and cruel attitudes towards slaves.
Explanation:
This idea is clearly supported by the case of Sophia Auld.
During the beginning of the text, Douglass describes her as <em>"a pious, warm, and tender-hearted woman"</em>. She was good and gentle with him, she was even teaching him how to read.
But she soon became as cruel as any slaveholder.
He describes her change as follows: <em>“The fatal poison of irresponsible power was already in her hands, and soon commenced its infernal work. That cheerful eye, under the influence of slavery, soon became red with rage; that voice, made all of sweet accord, changed to one of harsh and horrid discord; and that angelic face gave place to that of a demon. "
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This shows how despite being a sweet and understanding person, Sophia became inhuman because of the power of slavery.