Why did John Stuart Mill think lying could sometimes be morally required?

John Stuart Mill, a prominent utilitarian, argued that the morality of an action is determined by its ability to produce the greatest happiness for the greatest number of people. Because he believed that the moral value of an act lies entirely in its consequences, he concluded that there are specific circumstances where lying serves the general good more effectively than truth-telling. In such instances, he maintained that individuals may have a moral obligation to act dishonestly to maximize overall happiness.1

While Mill recognized that truthfulness is a vital general principle that tends to increase happiness, he did not believe utilitarians should attempt to calculate the consequences of every individual action. Instead, he suggested that people should generally be guided by established moral rules, such as the duty to be honest. However, he allowed that in special circumstances, one must consider whether an exception to these rules is necessary to achieve a better outcome. Ultimately, Mill’s framework prioritizes the ethical imperative of promoting human well-being, even when it requires departing from conventional standards of honesty.21