ABSTRACT
On Liberty sets out John Stuart Mill’s belief that individuality is essential to human well-being and must be defended using the “harm principle.” The most important minor themes at work in On Liberty come from the ideas being debated by Mill’s fellow philosophers and other scholars in the early nineteenth century. On Liberty builds on established thought to present nineteenth-century scholars with a fresh approach to the most enduring themes. The concept of progressive knowledge informs the whole of On Liberty, especially Mill’s defense of free speech. Mill agrees with John Milton, who in Areopagitica also argued that censoring new or unusual ideas makes open debate impossible. Mill starts by defending the open expression of different opinions and beliefs. He moves on to defend the fact that people have a range of preferences and may choose to try out many things in their lives.
