The purpose of the passage is to convey the idea that great suffering leads to happiness. Keller states that "most people measure their happiness in terms of…pleasure and material possession" or reaching some kind of "visible goal." She points out that if "happiness is to be so measured" then she "who cannot hear or see" would "have every reason to sit in a corner…and weep." However, she is "happy in spite of" her hardships and feels optimistic. She goes on to explain how once she felt hopeless and that "darkness lay on the face of all things" but that "love came and set my soul free" and now she knows "hope and joy." Keller’s language is meant to highlight the fact that Keller has not had the same advantages as others, yet she is still able to find joy in life. She then asks a rhetorical question: "Can anyone who has not escaped such captivity, who has felt the thrill and glory of freedom, be a pessimist?" This question emphasizes the idea that only by experiencing suffering and then breaking free from it, can one truly appreciate the feeling of joy. In the last sentence, Keller uses straightforward language to further her purpose by stating, "only by contact with evil could I have learned to feel by contrast the beauty of truth and love and goodness."
