In Frederick Douglass's Narrative, how does he develop the concept of paradox?

A paradox is somewhat like irony; paradox exists when something contradictory appears to be true or something that expresses a contradictory nature.  Basically, paradox can mean contrast.  For Douglass, he presents this idea when he creates antithesis with statements like "the wretchedness of slavery and the blessedness of freedom were before me," and "It was life and death for me." How can the two exist simultaneously? When he discusses his escape to the free state of New York, he initially feels happy, but he soon becomes paranoid and terrorized with the fear that he might be captured and returned to the south. A paradox exists because he should feel happy and should now be able to live a life of freedom since he is in a free state, but he cannot be free or happy because he remains trapped in his fears and distrust of those around him.