Thoreau wrote his famous essay, On the Duty of Civil Disobedience, as a protest against an unjust but popular war and the immoral but popular institution of slave-owning. He did more than write-he declined to pay his taxes, and was hauled off to gaol in consequence. Who can say how much this refusal of his hastened the end of the war and of slavery ? At the present day, intellectual detachment from the State, and individual defiance of its behests when these are opposed to conscience, are more difficult, and apparently more futile, than in Thoreau's time. The unit seems of less importance in the mass. It is all the more imperative, therefore, that the facts that the mass is composed of units and the conscience of the mass is the aggregate conscience of the units, and that the individual is still the sole responsible guardian of his own conscience and the co-guardian of the public conscience, should be fully recognized.