John Stuart Mill is one of those philosophers who never really becomes “historical,” because the world keeps reproducing the dilemmas he cared about in new forms. How should we balance individual freedom against collective well-being? When does a majority become a moral danger to minorities? What do we do with ideas we find offensive or frightening? How do we protect truth in a society that loves comfort more than inquiry? And beneath all of that, a quieter, more personal question: what kind of human being does a free society require, and what kind of society does a fully human life require?

Mill was born in London in 1806 and died in 1873. Those dates place him inside a Britain transforming itself with industrial speed. Factories multiply, cities swell, wealth concentrates, and the British state becomes more sophisticated and more intrusiv ...