John Stuart Mill was a 19th century English philosopher. Mill wrote supporting the defense of individual liberty in terms of social utility. Mill was concerned with defending the freedom of the individual against the power of society, and the freedom of minorities against the power of the majority. Mill developed the "harm principle", which states that each individual has the right to act as he wants, so long as these actions do not harm others. If the act only affects the person undertaking the action, then society has no right to intervene.