Prostitution in Relation to Our Marriage System--Marriage and Morality--The Definition of the Term "Morality"--Theoretical Morality--Its Division Into Traditional Morality and Ideal Morality--Practical Morality--Practical Morality Based on Custom--The Only Subject of Scientific Ethics--The Reaction Between Theoretical and Practical Morality--Sexual Morality in the Past an Application of Economic Morality--The Combined Rigidity and Laxity of This Morality--The Growth of a Specific Sexual Morality and the Evolution of Moral Ideals--Manifestations of Sexual Morality--Disregard of the Forms of Marriage--Trial Marriage--Marriage After Conception of Child--Phenomena in Germany, Anglo-Saxon Countries, Russia, etc.--The Status of Woman--The Historical Tendency Favoring Moral Equality of Women with Men--The Theory of the Matriarchate--Mother-Descent--Women in Babylonia--Egypt--Rome--The Eighteenth and Nineteenth Centuries--The Historical Tendency Favoring Moral Inequality of Woman--The Ambiguous Influence of Christianity--Influence of Teutonic Custom and Feudalism--Chivalry--Woman in England--The Sale of Wives--The Vanishing Subjection of Woman--Inaptitude of the Modern Man to Domineer--The Growth of Moral Responsibility in Women--The Concomitant Development of Economic Independence--The Increase of Women Who Work--Invasion of the Modern Industrial Field by Women--In How Far This Is Socially Justifiable--The Sexual Responsibility of Women and Its Consequences--The Alleged Moral Inferiority of Women--The "Self-Sacrifice" of Women--Society Not Concerned with Sexual Relationships--Procreation the Sole Sexual Concern of the State--The Supreme Importance of Maternity. CHAPTER X. MARRIAGE.