In normal individuals and in affectionate lovers the lassitude is of an agreeable nature. The serenity of the mind depends largely upon the intensity of the experienced libido. If the act is executed with great pleasure, it will give the nervous system a pleasurable excitement and will act as a helpful tonic upon the nerves. The blood under its animating influence flows more freely through the capillary vessels of the skin. The countenance becomes expanded, its expression brightens and its whole surface acquires the ruddy tint and genial glow of health. Every function seems to be gladdened by the tonic. It causes a universal expansion of vital action. The body feels buoyant and lively, and there is a consequent disposition to quick and cheerful muscular motions, as running, jumping, dancing, laughing, and singing. Furthermore, the act executed with a great intensity of pleasure serves to appease the sexual desire for a time and naturally leads to moderation. The serenity and well-being, following such an act, have a great influence upon the continuance of the lovers’ affections. An agreeable calmness will increase and even create attachment. Some conventional marriages turn for that reason into affectionate love-affairs. If the intensity of the libido is insignificant, a depression of the mind post concarnationem will result. Where coition is performed with aversion, without affection for the mate or with fear of infection or conception, it will act as a nerve-depressor, and a state of dejection will be the result. Such an act does not satisfy and appease the sexual desire. Like a distasteful meal that does not satiate, concubitus without pleasure or great affection creates desires for more sexual indulgences, keeps the nerves in a state of sexual excitement, and leads to many kinds of debauchery. Even if originally a good deal of affection existed, a sexually unsuitable match may reduce the intensity of the libido to a minimum. If then the languor is disagreeably felt, if the individual remains excited and is unable to sleep, and the following morning feels enervated, the former affection will gradually disappear, and a romantic love-affair of long duration may turn out a complete failure after marriage.[S] FOOTNOTES: