The harm principle is often explained as “your right to swing your fist ends where my nose begins.” In other words, people should be free to act as they wish as long as their actions do not cause harm to others.
The harm principle is central to the political philosophy of liberalism, which values individual rights and personal liberty. According to philosopher John Stuart Mill, “the only purpose for which power can be rightfully exercised over any member of a civilized community, against his will, is to prevent harm to others.”
For example, a government cannot make its citizens use a potential life-saving cancer treatment because no one else is harmed by a person’s decision to refuse this treatment. But a government can rightfully demand that its citizens be vaccinated in a pandemic in order to prevent the spread of a deadly virus to others.
According to Mill, disapproval or social dislike of an action such as being offended by what someone says or wears, is not enough to invoke the harm principle and limit personal freedoms. Critics counter that the harm principle is too vague or broad to be useful and does not adequately define harm. Also, unlike philosophical frameworks such as deontology or the ethics of care, critics point out that this principle was never meant to be a guide for human behavior.
Despite these criticisms, the harm principle has played a major role in many debates such as whether or not the government may punish homosexuality, hate speech, not wearing a seatbelt, and other similar issues.