The education of youth depends mostly upon impressions. Sometimes you may make a youth read books and that will not help; and sometimes you may tell the youth fifty times or a hundred times, "This is right", "This is not right", "This is not good", and he will never listen. But once you show him the phenomena, the example of what you are saying, and let the youth see with his own eyes what are the effects of different causes, then the teaching is given in an objective way; and in this manner wise guardians educate a youth.