President Obama gave the commencement address at Howard University on Saturday, May 7th. In his remarks, he alluded to "Mother to Son" a poem by Langston Hughes. Obama told the graduates, "Nobody promised you a crystal stair." He emphasized that life is not fair and that they will have to work hard to bring about societal change. In Hughes's poem, a mother says to her son, "Life for me ain't been no crystal stair." She shares her personal trials and encourages her son to persevere as she has. Read the full text of the poem here.