Full Idea
The will of the people practically means the will of the most numerous or the most active part of the people.
Gist of Idea
The will of the people is that of the largest or most active part of the people
Source
John Stuart Mill (On Liberty [1857], Ch.1)
Book Reference
Mill,John Stuart: 'Utilitarianism (including On Liberty etc)', ed/tr. Warnock,Mary [Fontana 1962], p.129
A Reaction
Hence the nicely coined modern phrase 'the silent majority', on whose behalf certain politicians, usually conservative, offer to speak. It is unlikely that the silent majority are actually deeply opposed to the views of the very active part.