 Mill countered this in 1843 in "A System of Logic" (fully titled "A System of Logic, Ratiocinative and Inductive, Being a Connected View of the Principles of Evidence, and the Methods of Scientific Investigation").In "Mill's Methods" (of induction), as in Herschel's, laws were discovered through observation and induction, and required empirical verification.Mill's "On Liberty" (1859) addresses the nature and limits of the power that can be legitimately exercised by society over the individual.