Mill's tone in "On Liberty," is rational and carefully measured, as evidenced by directness of Mill's arguments and the lack of ornamentation in his prose. Mill writes his philosophy in part as a warning about the potential missteps that a state and society can make, and therefore the clarity of his prose is of utmost importance. He lays out his case very carefully at the beginning of the essay, in an excellent example of the careful measure with which he argues.
"The nature and limits of the power which can be legitimately exercised by society over the individual," he writes, is
a question seldom stated, and hardly ever discussed, in general terms, but which profoundly influences the practical controversies of the age by its latent presence, and is likely soon to make itself recognised as the vital question of the future. It is so far from being new, that, in a certain sense, it has divided mankind, almost from the remotest ages; but in the stage of progress into which the more civilised portions of the species have now entered, it presents itself under new conditions, and requires a different and more fundamental treatment.
The rest of the essay continues in this plainspoken, deliberate tone, and Mill is unafraid to make sweeping statements about all of humanity and its history. There is some sense of foreboding about Mill's warnings, given that he sees the questions he addresses to be "vital" to humanity's future, but he is also clear that people possesses all the genius and perseverance necessary to better themselves and the world.
