That powerful assailant of Transcendentalism, John Stuart Mill, was not an evolutionist; but it was largely due to his liberal aid that the system of differentiation and integration was published. This generosity was consistent with his own position, that all opinions ought to have a hearing, and especially those which are novel and unpopular, for they are peculiarly likely to contain some exposure of ancient error or revelation of new truth. This fact was set forth with such ability in his book, _On Liberty_, in 1859, that several long passages were quoted in the public protest, delivered in Ohio five years later by Vallandigham, against the war then carried on for bringing back the seceded States. Mill holds that neither government nor public opinion ought to interfere with any individual, except "to prevent doing harm to others." He says, for instance, that there would be no tyranny in forcing parents to let their children have education enough to become safe members of society. Such a law could scarcely be justified by the principle of giving all the liberty to each compatible with the like liberty of all. Among the restrictions which Mill mentions as oppressive are those in England and America against selling liquor, gambling, and Sunday amusements. He admits the difficulty of deciding "how far liberty may be legitimately invaded for the prevention of crime." VII. It was in full conformity with the principles of Mill, Spencer, and Locke that the Constitution of Louisiana, as revised in 1879, declared that the only legitimate object of government "is to protect the citizen in the enjoyment of life, liberty, and property. When it assumes other functions, it is usurpation and oppression." Similar sentiments have been occasionally expressed in political platforms. Such narrow limits have not, so far as I know, ever been observed in the United States or in any other civilised land. Few people love liberty so much as not to be willing that the state should give them security against conflagration and contagious disease. There is also a general demand for such safety as is given by roads, streets, bridges, lighthouses, and life-saving stations. The necessity of hospitals, asylums, and poorhouses is manifest. If all this expense had to be met by public-spirited individuals, it is probable that their wealth would prove insufficient. It is further necessary for the public safety that there should be compulsory vaccination during epidemics of smallpox, confinement of dangerous lunatics and tramps, rescue of children from vicious parents, and maintenance of what ought not to be called compulsory but guaranteed education. Marriage has to be made binding for the protection of mothers as well as children. The thirst for drink needs at least as much restraint as is kept up in Scandinavia. And the tendency of bad money to drive out good is strong enough to justify laws against circulation of depreciated currency.