Mental exercise, like physical exercise, has sometimes been advocated as a method of calming sexual excitement, but it seems to be equally equivocal in its action.  If it is profoundly interesting and exciting it may stir up rather than lull the sexual emotions.  If it arouses little interest it is unable to exert any kind of influence.  This is true even of mathematical occupations which have been advocated by various authorities, including Broussais, as aids to sexual hygiene.[101] “I have tried mechanical mental work,” a lady writes, “such as solving arithmetical or algebraic problems, but it does no good; in fact it seems only to increase the excitement.”  “I studied and especially turned my attention to mathematics,” a clergyman writes, “with a view to check my sexual tendencies.  To a certain extent I was successful.  But at the approach of an old friend, a voice or a touch, these tendencies came back again with renewed strength.  I found mathematics, however, the best thing on the whole to take off my attention from women, better than religious exercises which I tried when younger (twenty-two to thirty).”  At the best, however, such devices are of merely temporary efficacy.

It is easier to avoid arousing the sexual impulses than to impose silence on them by hygienic measures when once they are aroused.  It is, therefore, in childhood and youth that all these measures may be most reasonably observed in order to avoid any premature sexual excitement.  In one group of stolidly normal children influences that might be expected to act sexually pass away unperceived.  At the other extreme, another group of children are so neurotically and precociously sensitive that no precautions will preserve them from such influences.  But between these groups there is another, probably much the largest, who resist slight sexual suggestions but may succumb to stronger or longer influences, and on these the cares of sexual hygiene may profitably be bestowed.[102]

After puberty, when the spontaneous and inner voice of sex may at any moment suddenly make itself heard, all hygienic precautions are liable to be flung to the winds, and even the youth or maiden most anxious to retain the ideals of chastity can often do little but wait till the storm has passed.  It sometimes happens that a prolonged period of sexual storm and stress occurs soon after puberty, and then dies away although there has been little or no sexual gratification, to be succeeded by a period of comparative calm.  It must be remembered that in many, and perhaps most, individuals, men and women, the sexual appetite, unlike hunger or thirst, can after a prolonged struggle, be reduced to a more or less quiescent state which, far from injuring, may even benefit the physical and psychic vigor generally.  This may happen whether or not sexual gratification has been obtained.  If there has never been any such gratification, the struggle is less severe and sooner over, unless the