Nevertheless, the men who consciously sacrifice the women are in a minority. Most men act in ignorance. Our code, however, has blindly sacrificed not only the woman, but with her the happiness of the majority of men, who, in total ignorance of its meaning and results, have grown up thinking that women should submit to regularly frequent, or even nightly, intercourse. For the sake of a few moments of physical pleasure they lose realms of ever-expanding joy and tenderness; and while men and women may not realise the existence of an untrodden paradise, they both suffer, if only half consciously, from being shut out from it. Before making some suggestions which may help married people to find not only a _via media_ of mutual endurance, but a _via perfecta_ of mutual joy, it is necessary to consider a few points about the actual nature of man's "desire." In the innumerable books addressed to the young which I have read, I have not found one which gives certain points regarding the meaning of the male sex-phenomena which must be grasped before it is possible to give rational guidance to intelligent young men. The general ground plan of our physiology is told to us in youth because it so obviously is right for us to know it accurately and in a clean scientific way, rather than to be perpetually perplexed by fantastic imaginings. But the physiology of our most profoundly disturbing functions is ignored--in my opinion, criminally ignored. To describe the essentials, simple, direct and scientific language is necessary, though it may surprise those who are accustomed only to the hazy vagueness which has led to so much misapprehension of the truth. Every mating man and woman should know the following: The sex organs of a man consist not only of the tissues which give rise to the living, moving, ciliated cells, the _sperms_, and of the penis through which they pass and by means of which they are directed into the proper place for their deposition, the woman's vagina. Associated with these primary and essential structures there are other tissues and glands which have numerous subsidiary but yet very important parts to play; some of which influence almost every organ in the body. Man's penis, when unstimulated, is soft, small and drooping. But when stimulated, either by physical touch which acts through the nerves and muscles directly, or indirectly through messages from the brain, it increases greatly in size, and becomes stiff, turgid and erect. Many men imagine that the turgid condition of an erection is due to the local accumulation of sperms, and that these can only be naturally got rid of by an ejaculation. This is entirely wrong. The enlargement of the penis is not at all due to the presence of actual sperm, but is due to the effects of the nervous reaction on the blood-vessels, leading to the filling, principally of the _veins_, and much less of the arteries. As the blood enters but does not