Imagine that you lived in 1840 and saw a man reading The Liberator. What can be most likely assumed about that person?
He supported women's suffrage.
He opposed women's suffrage.
He supported the abolition of slavery.
He opposed the abolition of slavery.
If you lived in 1840 and saw a man reading The Liberator, you could assume that "He supported the abolition of slavery", since this publication was meant to support the abolition movement.