"Reading a broad range of literature is, in our opinion, the best way to train your mind and to become a critical thinker.....we wanted to create a list that if completed would leave the individual [young man] with a range of perspectives that [would] allow them to come to educated conclusions about the topic." (Jack Prenter, Known Man).
The young man is defined as being between the ages of 15 and 30 years old. Prenter adds: "that's not to say that this list isn't suitable for everyone".
BTW, Known Man appears to be a website for male hipsters, such as the one in the list image.