This sexual difference means not only that the girl must be intolerant of improper advances, but also that for her own sake and that of her sister women she must beware of conduct, attitudes, or forms of dress that tend unduly to excite the sexual impulses in boys and men.

In view of the enormous morbidity and mortality inflicted upon innocent women and their children by sexual disease, the girl should learn the main facts concerning the nature, effects, and incidence of gonorrhea and syphilis.  Health certificates of prospective bridegrooms will probably be more easily enforced if such intelligence becomes general.  The time for such instruction is difficult to state, and would vary with the social environment; probably late adolescence would be early enough in most cases; earlier information is indispensable for girls who by reason of their economic or social status are peculiarly exposed to sexual temptation and danger.

Training for motherhood, a great gap in our educational system, is a closely related theme, of incomparable importance, but beyond the scope of this work.

(2) Boys should learn early the rewards of continence:  that the conservation of the sexual secretions is the indispensable condition of manly growth in stature, muscular powers, voice, heart, and brain.  They should learn the possibility and healthiness of continence—­always understanding that mental continence is the prerequisite of physical continence.

They should know in good time that nocturnal emissions are quite normal, when not too frequent, and indicate not lost manhood or the danger of it, but merely the fact that the sexual glands are now for the first time all developed and active.  This is one of the simplest and most commonplace facts in the whole range of sex knowledge, yet, through ignorance of it, unknown multitudes of boys have suffered anxiety sometimes amounting to terror, have become moody and dejected, lost interest in work and studies; and finally thousands of them, ashamed to ask counsel or enlightenment from any decent source, have had recourse to the venereal quack, who so artfully spreads his snares for them in daily paper and widely circulated pamphlet.  Once the victim is in his hands there is almost no limit to the evil that may result.[38] High-school principals tell of watching the faces of their boys during a lecture on sex hygiene and noting the visible signs of relief and new hope when the lecturer explained the true nature and meaning of emissions.

So far as the so-called “sexual necessity” is concerned, let boys understand that it is unknown among animals; that its completest embodiment is found in degenerates and imbeciles; and that athletes, thinkers, priests, scholars, warriors, the finest men of every type, hold their passions strictly subject to their wills.  Let them know that the world is well supplied with wretches whom this very “sexual necessity” has robbed of their precious virile powers, but that the cases of impotence through chastity are certainly unproved and probably non-existent except in the imagination of people who want to believe in them.  And finally that numberless fathers of big healthy families were as chaste as the wives who bore their children.