I cannot discover that Locke fathers the pet doctrine of modern Liberalism, that the toleration of error is a good thing in itself, and to be reckoned among the cardinal virtues; on the contrary, in this very “Letter on Toleration” he states in the clearest language that “No opinion contrary to human society, or to those moral rules which are necessary to the preservation of civil society, are to be tolerated by the magistrate.”  And the practical corollary which he draws from this proposition is that there ought to be no toleration for either Papists or Atheists.

After Locke’s time the negative view of the functions of Government gradually grew in strength, until it obtained systematic and able expression in Wilhelm von Humboldt’s “Ideen,"[1] the essence of which is the denial that the State has a right to be anything more than chief policeman.  And, of late years, the belief in the efficacy of doing nothing, thus formulated, has acquired considerable popularity for several reasons.  In the first place, men’s speculative convictions have become less and less real; their tolerance is large because their belief is small; they know that the State had better leave things alone unless it has a clear knowledge about them; and, with reason, they suspect that the knowledge of the governing power may stand no higher than the very low watermark of their own.

[Footnote 1:  An English translation has been published under the title of “Essay on the Sphere and Duties of Government.”]

In the second place, men have become largely absorbed in the mere accumulation of wealth; and as this is a matter in which the plainest and strongest form of self-interest is intensely concerned, science (in the shape of Political Economy) has readily demonstrated that self-interest may be safely left to find the best way of attaining its ends.  Rapidity and certainty of intercourse between different countries, the enormous development of the powers of machinery, and general peace (however interrupted by brief periods of warfare), have changed the face of commerce as completely as modern artillery has changed that of war.  The merchant found himself as much burdened by ancient protective measures as the soldier by his armour—­and negative legislation has been of as much use to the one as the stripping off of breast-plates, greaves, and buff-coat to the other.  But because the soldier is better without his armour it does not exactly follow that it is desirable that our defenders should strip themselves stark naked; and it is not more apparent why laissez-faire—­great and beneficial as it may be in all that relates to the accumulation of wealth—­should be the one great commandment which the State is to obey in all other matters; and especially in those in which the justification of laissez-faire, namely, the keen insight given by the strong stimulus of direct personal interest, in matters clearly understood, is entirely absent.