The romantic theory of affinities rests upon an immature [p311] theory of desire. It springs from an infantile belief that the success of love is in the satisfactions which the other person provides. What this really means is that in childlike fashion the lover expects his mistress to supply him with happiness. But in the adult world that expectation is false. Because nine-tenths of the cause, as Mr. Santayana says, are in the lover for one-tenth that may be in the object, it is what the lover does about that nine-tenths which is decisive for his happiness. It is the claim, therefore, of those who uphold the ideal of marriage as a full partnership, and reject the ideal which would separate love as an art from parenthood as a vocation, that in the home made by a couple who propose to see it through, there are provided the essential conditions under which the passions of men and women are most likely to become mature, and therefore harmonious and disinterested. 7. _The Schooling of Desire_ They need not deny, indeed it would be foolish as well as cruel for them to underestimate, the enormous difficulty of achieving successful marriages under modern conditions. For with the dissolution of authority and compulsion, a successful marriage depends wholly upon the capacity of the man and the woman to make it successful. They have to accomplish wholly by understanding and sympathy and disinterestedness of purpose what was once in a very large measure achieved by habit, necessity, and the absence of any practicable alternative. It takes two persons to make a successful marriage in the modern world, and that fact more than doubles its difficulty. For these reasons alone the modern state ought to do what it [p312] would none the less be compelled to do: it ought to provide decent ways of retreat in case of failure. But if it is the truth that the convention of marriage correctly interprets human experience, whereas the separatist conventions are self-defeating, then the convention of marriage will prove to be the conclusion which emerges out of all this immense experimenting. It will survive not as a rule of law imposed by force, for that is now, I think, become impossible. It will not survive as a moral commandment with which the elderly can threaten the young. They will not listen. It will survive as the dominant insight into the reality of love and happiness, or it will not survive at all. That does not mean that all persons will live under the convention of marriage. As a matter of fact in civilized ages all persons never have. It means that the convention of marriage, when it is clarified by insight into reality, is likely to be the hypothesis upon which men and women will ordinarily proceed. There will be no compulsion behind it except the compulsion in each man and woman to reach a true adjustment of his life.