Another thing is necessary for good sex instruction. Up till a little while ago it was the custom of workers with boys to caution the lads against self-abuse. They used all kinds of colored slides and fearful examples to impress on the boy the horror of the act, and very often inflamed the boy to exactly the thing they were shooing him from. But today we are learning the fact that the positive is of more force than the negative, and that the "thou shalt" is better than the "thou shalt not." There is a real reason why the later adolescent boy should give no attention to the "thou shalt not," and so fall into the snare of the negative; for it is the law of his being to "prove all things." It is far better to lay emphasis on the legitimate purposes of the boy's sex life, the glory it gives him and the beauty of the self-sacrifice it begets, than to say a single word on the other side. I have found it a good thing to refer to the practice of self-abuse of any kind as a sure sign of weak mentality, and this has produced a greater impression than anything else that I have formerly said. Boys, it should be remembered, have brains and are really able to think. When they act wrongly it is so often from lack of knowledge or because of wrong knowledge. If I were to teach a boy my business I should tell him everything that would make the business better, and say nothing of how to put it "to the bad." Now what would we all do if our business was to help boys to live clean lives, speak truth, bless the community with unimpaired manhood and honor God with their united physical powers? =Methods of Instruction= It is necessary to keep in mind the stage of development of the boy. It certainly would be foolish to tell a lad of eight years the facts that should be given to a sixteen-year-old. Great tact and intelligence, coupled with a knowledge of the stages of physical growth that a boy is passing through, are necessary. A boy of under twelve years should be approached biologically: the sex element in nature study should be gradually disclosed to him. In this period, when the spirit of curiosity is strong in the boy and he is continually asking questions on the mystery of life--for instance, how the stork or the doctor can bring the little brother or sister--it is the best thing to answer the question with just enough truthful information to satisfy. Great harm may be done by piling the mind of the child with facts that cannot but be misunderstood. In the enthusiasm for doing things right, there must be a guard against going too far.