Kropotkin’s “Ethics: Origin and Development,†is, in a sense, a continuation of his well-known work, “Mutual Aid as a Factor of Evolution.†The basic ideas of the two books are closely connected, almost inseparable, in fact: — the origin and progress of human relations in society. Only, in the “Ethics†Kropotkin approaches his theme through a study of the ideology of these relations. The Russian writer removes ethics from the sphere of the speculative and metaphysical, and brings human conduct and ethical teaching back to its natural environment: the ethical practices of men in their everyday concerns — from the time of primitive societies to our modern highly organized States. Thus conceived, ethics becomes a subject of universal interest; under the kindly eyes and able pen of the great Russian scholar, a subject of special and academic study becomes closely linked to whatever is significant in the life and thought of all men.