Dead Poets Society features a myriad of famous poets and their works. As one example, John Keating tells the more daring among his students that they may refer to him as "O Captain! My Captain!" a reference to Walt Whitman's poem of the same title. Born in 1819, Walt Whitman considered the American Civil War one of the central events of his life. A staunch Unionist throughout the conflict, he grew to love President Abraham Lincoln after an initially indifferent opinion of him. He wrote "O Captain! My Captain!" about Lincoln following his assassination. The poem, one of the most well-known classic poems of today, is classified as an elegy to the late president. That the students use it to refer to Mr. Keating, particularly in the iconic final scene of the film in which they proclaim it as they stand on their desks, draws a direct parallel between Lincoln and Keating as revered men gone too soon—in Lincoln's case, referring to his death, and in Keating's, to his being fired.
The boys invoke a famous quote by Henry David Thoreau at the beginning of each meeting of the Dead Poets Society: "I went to the woods because I wished to live deliberately, to front only the essential facts of life..." The quote is taken from Thoreau's book Walden, which he wrote about spending more than two years on his own in a small cabin by Walden Pond in Concord, Massachusetts. The book focuses on living simply and with purpose, and has been called everything from a social experiment to satire to a manual for self-reliance. No doubt, the cited quote mirrors what the boys themselves do through the Dead Poets Society: going to the woods to recite poetry to one another, and eventually to express themselves in many ways, including storytelling, dancing, and playing the saxophone. Many of the boys feel that the academic shackles that hold them are unjust, and some, especially Neil, fear that when it's their time to die and begin "fertilizing daffodils," as Mr. Keating glibly put it, that they will "discover that [they] had not lived." The quote is therefore an effective and appropriate one to use to begin each of the Society's meetings.