Final answer:
John Stuart Mill's essay On Liberty articulates the harm principle, emphasizing that government intervention should only occur to prevent harm to others, and promotes individual freedom. Mill's utilitarian greatest happiness principle also supports this view, arguing that actions should aim for the general happiness.
Step-by-step explanation:
The principle that John Stuart Mill argues for in his essay On Liberty is a fundamental principle of liberalism: the harm principle. In essence, this principle asserts that the government should only limit the actions of individuals if those actions cause harm to others. He champions individual freedom and autonomy, promoting the idea that adults should be free to make their own choices, regardless of personal risk, unless those choices harm others. Alongside this, he highlights the need for open debate and the expression of all views, contributing to the betterment of society through the rejection of dangerous ideas and fostering progress.
Mill's greatest happiness principle complements his harm principle by positing that actions are right if they produce the most happiness for the greatest number. This utilitarian approach undergirds his arguments for limited government interference in individual lives to ensure that societal actions contribute to the overall happiness of the population. In advocating for personal liberty, Mill also contributed to the discourse on women's rights, arguing for the inclusion of women in societal reforms and the expansion of voting rights to more demographics, thus underlining the broader applications of his principles of liberty and utility.