Love, in its ideal form, must be founded on mental qualities. In man the mental qualities are of the greatest value. The supreme survival value for man is his intelligence. The possessors of artistic or literary composition, of mechanical skill, of calculating ability, of energy or general mental ability are seldom or never endowed at the same time with physical qualities. It was brain not brawn that saved man in his struggle for existence. The cult of the muscle as against intelligence would destroy man. The physically fittest is not always the best of men. Even the animals, in their natural surroundings, live by their wits rather than by force of bone and muscle; and it was man’s wits and will that enabled him to increase and multiply as no other animal. Physical weapons of defense and offense have disappeared in man because his intelligence makes them superfluous. In the human species mind is master of matter. Man has staked his all upon mind. The emergence and dominance of mind have enabled the human species to ascend through struggle and internecine war to the highest scale of animal life, although it is physically one of the feeblest among the species of the higher animals. The increasing dominance of mind over matter is the reason that nowadays mental qualities dominate all else in man’s living activities. Hence ideal love must also be based upon mental qualities. Then it will be everlasting. The soul once allied with its mate can change no more. One of the mysteries of true love is the absolute impossibility to duplicate the lover. The soul is thus the essential part in true love. But when in the selection of the mates the physical factors only, such as stature, beauty, strength and health, play the most important rôle, when the senses form the chief part of the compound feeling, love will not long survive possession, and matrimonial happiness, founded upon monetary or social considerations, will pass like a shadow. The idol is soon destroyed. When, thereupon, the heart is disillusioned by the contact with the grim realities of existence, when it is deadened by the habitude of a fixed affection, coupled with incompatibility of tastes, when hardened by experience with the meanness of the world, then men and women attempt to find elsewhere a soul which they hope will desire to know more of their own, and in which they trust to discover a greater and more lasting happiness. But not being able to ask their own hearts, and guided only by the contradictory ideals they have been imbued with in their youth, the second choice and all the others, following the same, will generally turn out to be also delusions in which the perfect communion of hearts will again be absent. Men will then try to bury their unsatisfied longing for true affection in the exaggerated occupation with business or to drown their vehement unrequited love-yearnings in drink and other narcotics. The fate of the woman is even more tragic.